#!/usr/bin/perl
# 
# This program will manage servers; Changing RAM, CPU cores, Growing virtual disks, adding virtual disks, 
# inserting and ejecting ISO images into virtual optical media.
# 
# Exit codes;
# 0 = Normal exit.
# 1 = No database connection.
# 
# TODO: 
# 
# USAGE:
# - Show
#   - anvil-manage-server-storage --server srv01-fs37
# - ISO
#   - anvil-manage-server-storage --server srv01-fs37 --optical sda --insert /mnt/shared/files/CentOS-5.11-x86_64-bin-DVD-1of2.iso
#   - anvil-manage-server-storage --server srv01-fs37 --optical sda --eject
# - Disk
#   - anvil-manage-server-storage --server srv01-fs37 --disk vdb --grow {+10GiB,150GiB}
# 

use strict;
use warnings;
use Anvil::Tools;
require POSIX;
use Term::Cap;
use Text::Diff;
use Data::Dumper;

my $THIS_FILE           =  ($0 =~ /^.*\/(.*)$/)[0];
my $running_directory   =  ($0 =~ /^(.*?)\/$THIS_FILE$/)[0];
if (($running_directory =~ /^\./) && ($ENV{PWD}))
{
	$running_directory =~ s/^\./$ENV{PWD}/;
}

# Turn off buffering so that the pinwheel will display while waiting for the SSH call(s) to complete.
$| = 1;

my $anvil = Anvil::Tools->new();

### TODO: Remove this before final release
$anvil->Log->level({set => 2});
$anvil->Log->secure({set => 1});
##########################################

# Read switches (target ([user@]host[:port]) and the file with the target's password.
$anvil->Get->switches({list => [
	"add", 
	"anvil", 
	"confirm", 
	"disk", 
	"eject", 
	"grow", 
	"insert", 
	"optical", 
	"server", 
	"storage-group", 
	], man => $THIS_FILE});
$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => $anvil->data->{switches}});
$anvil->Log->entry({source => $THIS_FILE, line => __LINE__, level => 2, key => "log_0115", variables => { program => $THIS_FILE }});

# Connect to the database(s). If we have no connections, we'll proceed anyway as one of the 'run_once' tasks
# is to setup the database server.
$anvil->Database->connect();
$anvil->Log->entry({source => $THIS_FILE, line => __LINE__, level => 3, secure => 0, key => "log_0132"});
if (not $anvil->data->{sys}{database}{connections})
{
	# No databases, update the job, sleep for a bit and then exit. The daemon will pick it up and try 
	# again after we exit.
	$anvil->Log->entry({source => $THIS_FILE, line => __LINE__, 'print' => 1, level => 0, priority => "err", key => "error_0305"});
	sleep 10;
	$anvil->nice_exit({exit_code => 1});
}

$anvil->Database->get_hosts();
$anvil->Database->get_anvils();
$anvil->Database->get_servers();

if ($anvil->data->{switches}{anvil})
{
	# Make sure they asked for a real anvil.
	$anvil->Get->anvil_from_switch({string => $anvil->data->{switches}{anvil}});
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		"switches::anvil_name" => $anvil->data->{switches}{anvil_name},
		"switches::anvil_uuid" => $anvil->data->{switches}{anvil_uuid},
	}});
}

if (not $anvil->data->{switches}{server})
{
	# Show the list of servers.
	show_server_list($anvil);
	print "\nPlease specify which server you want to modify using '--server <name or uuid>'.\n\n";
	$anvil->nice_exit({exit_code => 0});
}

validate_server($anvil);

if ($anvil->data->{switches}{optical})
{
	manage_optical($anvil);
}
elsif ($anvil->data->{switches}{disk})
{
	manage_disk($anvil);
}
else
{
	show_server_details($anvil);
}

$anvil->nice_exit({exit_code => 0});


#############################################################################################################
# Functions                                                                                                 #
#############################################################################################################

sub load_storage
{
	my ($anvil) = @_;
	
	# Host and server
	my $short_host_name = $anvil->Get->short_host_name;
	my $server_name     = $anvil->data->{switches}{server_name};
	
	# We need to know which volume groups the disks are on so that we can report how much free space is 
	# available for either growing or adding a disk.
	$anvil->Get->available_resources({
		debug      => 2,
		anvil_uuid => $anvil->data->{switches}{anvil_uuid},
	});
	
	# Load LVM and Storage Group data
	$anvil->Database->get_lvm_data({debug => 2});
	
	# Load DRBD data from the database.
	$anvil->Database->get_drbd_data({debug => 2});
	
	# Load DRBD resource data so that we can map DRBD resources / volumes to volume groups.
	my $drbd_resource = "";
	foreach my $device_path (sort {$a cmp $b} keys %{$anvil->data->{server}{$short_host_name}{$server_name}{device}})
	{
		my $on_lv         = $anvil->data->{server}{$short_host_name}{$server_name}{device}{$device_path}{on_lv};
		   $drbd_resource = $anvil->data->{server}{$short_host_name}{$server_name}{device}{$device_path}{resource};
		my $device_target = $anvil->data->{server}{$short_host_name}{$server_name}{device}{$device_path}{target};
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			's1:device_path'   => $device_path, 
			's2:on_lv'         => $on_lv,
			's3:drbd_resource' => $drbd_resource, 
			's4:device_target' => $device_target, 
		}});
	}
	# There should only ever be one, but it's not impossible for there to be multiple.
	foreach my $drbd_resource (sort {$a cmp $b} keys %{$anvil->data->{server}{$short_host_name}{$server_name}{drbd}{resource}})
	{
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { drbd_resource => $drbd_resource }});
		
		# Get the DRBD volume data
		load_drbd_data($anvil, $drbd_resource);
	}
	
	return($drbd_resource);
}

sub manage_disk
{
	my ($anvil) = @_;
	
	my $anvil_uuid      = defined $anvil->data->{switches}{anvil_uuid} ? $anvil->data->{switches}{anvil_uuid} : $anvil->Cluster->get_anvil_uuid();
	my $short_host_name = $anvil->Get->short_host_name;
	my $server_name     = $anvil->data->{switches}{server_name};
	my $from_source     = get_definition_source($anvil);
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		anvil_uuid      => $anvil_uuid, 
		short_host_name => $short_host_name,
		server_name     => $server_name, 
		from_source     => $from_source, 
	}});
	if (not $anvil->data->{switches}{disk})
	{
		# If there's only one optical drive, select it automatically
		my $count = keys %{$anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{disk}{target}};
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { count => $count }});
		if ($count == 1)
		{
			foreach my $device_target (sort {$a cmp $b} keys %{$anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{disk}{target}})
			{
				$anvil->data->{switches}{disk} = $device_target;
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					"switches::drive" => $anvil->data->{switches}{disk},
				}});
				last;
			}
		}
		
		if (not $anvil->data->{switches}{disk})
		{
			# Can't proceed.
			print "\n[ Error ] - Please indicate the disk drive to work with using '--disk --drive <target_device>'.\n\n";
			show_server_details($anvil);
			$anvil->nice_exit({exit_code => 1});
		}
	}
	
	my $drbd_resource = load_storage($anvil);
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { drbd_resource => $drbd_resource }});
	foreach my $host_type ("node", "dr")
	{
		foreach my $short_host_name (sort {$a cmp $b} keys %{$anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}})
		{
			my $host_uuid = $anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}{$short_host_name}{host_uuid};
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				's1:short_host_name' => $short_host_name,
				's2:host_uuid'       => $host_uuid, 
			}});
			foreach my $volume_number (sort {$a cmp $b} keys %{$anvil->data->{drbd_resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}})
			{
				my $device_path  = $anvil->data->{drbd_resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$volume_number}{device_path};
				next if $device_path eq "DELETED";
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					's1:volume_number' => $volume_number,
					's2:device_path'   => $device_path, 
				}});
				
				my $device_minor = $anvil->data->{drbd_resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$volume_number}{device_minor};
				my $volume_size  = $anvil->data->{drbd_resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$volume_number}{volume_size};
				my $backing_disk = $anvil->data->{new}{resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$volume_number}{backing_disk};
				my $meta_disk    = $anvil->data->{new}{resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$volume_number}{meta_disk};
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					's1:device_minor'  => $device_minor, 
					's2:volume_size'   => $volume_size, 
					's3:backing_disk'  => $backing_disk, 
					's4:meta_disk'     => $meta_disk, 
				}});
				
				# Which volume group is the backing device in?
				foreach my $this_scan_lvm_lv_name (sort {$a cmp $b} keys %{$anvil->data->{lvm}{host_name}{$short_host_name}{lv}})
				{
					next if not $this_scan_lvm_lv_name;
					my $this_scan_lvm_lv_path  = $anvil->data->{lvm}{host_name}{$short_host_name}{lv}{$this_scan_lvm_lv_name}{scan_lvm_lv_path}; 
					my $this_scan_lvm_lv_on_vg = $anvil->data->{lvm}{host_name}{$short_host_name}{lv}{$this_scan_lvm_lv_name}{scan_lvm_lv_on_vg}; 
					my $this_scan_lvm_lv_uuid  = $anvil->data->{lvm}{host_name}{$short_host_name}{lv}{$this_scan_lvm_lv_name}{scan_lvm_lv_uuid};
					$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
						's1:this_scan_lvm_lv_name'  => $this_scan_lvm_lv_name, 
						's2:this_scan_lvm_lv_path'  => $this_scan_lvm_lv_path,
						's3:this_scan_lvm_lv_on_vg' => $this_scan_lvm_lv_on_vg, 
						's4:this_scan_lvm_lv_uuid'  => $this_scan_lvm_lv_uuid, 
					}});
					
					if ($backing_disk eq $this_scan_lvm_lv_path)
					{
						# What's the VG's UUID? 
						$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
							's1:short_host_name'        => $short_host_name, 
							's2:this_scan_lvm_lv_on_vg' => $this_scan_lvm_lv_on_vg, 
						}});
						if (exists $anvil->data->{lvm}{host_name}{$short_host_name}{vg}{$this_scan_lvm_lv_on_vg})
						{
							my $scan_lvm_vg_uuid   = $anvil->data->{lvm}{host_name}{$short_host_name}{vg}{$this_scan_lvm_lv_name}{scan_lvm_vg_uuid};
							my $storage_group_uuid = $anvil->data->{lvm}{host_name}{$short_host_name}{vg}{$this_scan_lvm_lv_name}{storage_group_uuid};
							$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
								's1:scan_lvm_vg_uuid'   => $scan_lvm_vg_uuid, 
								's2:storage_group_uuid' => $storage_group_uuid, 
							}});
						}
					}
				}
				
				# How much space can this LV grow into (this factors DR is already protected).
				$anvil->data->{server_name}{$server_name}{drbd_resource}{$drbd_resource}{volume}{$volume_number}{free_space} = get_max_free_space($anvil, $drbd_resource, $volume_number);
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					"server_name::${server_name}::drbd_resource::${drbd_resource}::volume::${volume_number}::free_space" => $anvil->data->{server_name}{$server_name}{drbd_resource}{$drbd_resource}{volume}{$volume_number}{free_space}." (".$anvil->Convert->bytes_to_human_readable({'bytes' => $anvil->data->{server_name}{$server_name}{drbd_resource}{$drbd_resource}{volume}{$volume_number}{free_space}}).")", 
				}});
			}
		}
	}
	
	if (($anvil->data->{switches}{grow}) or ($anvil->data->{switches}{remove}))
	{
		my $device_target = $anvil->data->{switches}{disk};
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { device_target => $device_target }});
		
		if ($anvil->data->{switches}{disk} eq "#!SET!#")
		{
			# User didn't specify a device.
			show_server_details($anvil);
			print "\n[ Error ] - Please specify the disk drive target you want to work on.\n";
			$anvil->nice_exit({exit_code => 1});
		}
		elsif (not exists $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{disk}{target}{$device_target})
		{
			# Invalid device target
			show_server_details($anvil);
			print "\n[ Error ] - The disk drive target: [".$device_target."] wasn't found.\n";
			$anvil->nice_exit({exit_code => 1});
		}

		my $device           = "disk";
		my $alias            = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{alias};
		my $boot_order       = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{boot_order};
		my $say_boot         = $boot_order eq "99" ? "--" : sprintf("%02d", $boot_order);
		my $type             = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{type};
		my $address_type     = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{address}{type};
		my $address_bus      = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{address}{bus};
		my $driver_name      = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{driver}{name};
		my $device_bus       = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{device_bus};
		my $driver_type      = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{driver}{type};
		my $address_domain   = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{address}{domain};
		my $address_slot     = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{address}{slot};
		my $address_function = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{address}{function};
		my $device_path      = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{path};
		my $driver_io        = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{driver}{io};
		my $driver_cache     = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{driver}{cache};
		my $on_lv            = $anvil->data->{server}{$short_host_name}{$server_name}{device}{$device_path}{on_lv};
		my $drbd_volume      = $anvil->data->{lvm}{host_name}{$short_host_name}{lv_path}{$on_lv}{drbd}{volume};
		my $max_free_space   = $anvil->data->{server_name}{$server_name}{drbd_resource}{$drbd_resource}{volume}{$drbd_volume}{free_space};
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			's01:device_target'    => $device_target,
			's02:alias'            => $alias, 
			's03:boot_order'       => $boot_order,
			's04:say_boot'         => $say_boot, 
			's05:type'             => $type, 
			's06:address_type'     => $address_type, 
			's07:address_bus'      => $address_bus, 
			's08:driver_name'      => $driver_name, 
			's09:device_bus'       => $device_bus, 
			's10:driver_type'      => $driver_type, 
			's11:address_domain'   => $address_domain,
			's12:address_slot'     => $address_slot, 
			's13:address_function' => $address_function, 
			's14:device_path'      => $device_path, 
			's15:driver_io'        => $driver_io, 
			's16:driver_cache'     => $driver_cache, 
			's17:on_lv'            => $on_lv, 
			's18:drbd_volume'      => $drbd_volume, 
			's19:max_free_space'   => $max_free_space." (".$anvil->Convert->bytes_to_human_readable({'bytes' => $max_free_space}).")",
		}});
		#print "- Target: [".$device_target."], boot: [".$say_boot."], path: [".$device_path."], cache: [".$driver_cache."], driver type: [".$driver_type."]\n";
		print "- Target: [".$device_target."], boot: [".$say_boot."], path: [".$device_path."], Available space: [".$anvil->Convert->bytes_to_human_readable({'bytes' => $max_free_space})."]\n";
		
		# What are we doing?
		if ($anvil->data->{switches}{grow})
		{
			manage_disk_grow($anvil, $drbd_resource, $drbd_volume, $max_free_space);
		}
	}
	elsif ($anvil->data->{switches}{add})
	{
		manage_disk_add($anvil, $drbd_resource);
	}
	
	return(0);
}

sub manage_disk_add
{
	my ($anvil, $drbd_resource) = @_;
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { drbd_resource => $drbd_resource }});
	
	my $anvil_uuid      = defined $anvil->data->{switches}{anvil_uuid} ? $anvil->data->{switches}{anvil_uuid} : $anvil->Cluster->get_anvil_uuid();
	my $short_host_name = $anvil->Get->short_host_name;
	my $server_name     = $anvil->data->{switches}{server_name};
	my $from_source     = get_definition_source($anvil);
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		anvil_uuid      => $anvil_uuid, 
		short_host_name => $short_host_name,
		server_name     => $server_name, 
		from_source     => $from_source, 
	}});
	
	# Are they asking for an available amount of space?
	my $error_note = q|
[ Note ]  - The size can be in percent, ie: '50%' or '100%', a number in bytes, or a human-readable size.
          - Human readable sizes must NOT have a space between the number and letter suffix. Also, base2 
          - vs base10 notation! Ie: '1GiB' = 1,073,741,824 bytes', '1GB' == '1,000,000,000 bytes'. A single
          - letter used to denote size will be interpreted as base2. ie: '1G == 1GiB'.
|;
	
	# Do we have a storage group?
	if (not $anvil->data->{switches}{'storage-group'})
	{
		print "Please specify a storage group to use to add the new drive to.\n";
		short_storage_groups($anvil, $anvil_uuid);
		$anvil->nice_exit({exit_code => 1});
	}
	
	# Make sure that the passed
	my $storage_group_switch = $anvil->data->{switches}{'storage-group'};
	my $storage_group_uuid   = "";
	my $storage_group_name   = "";
	if (exists $anvil->data->{storage_groups}{anvil_uuid}{$anvil_uuid}{storage_group_name}{$storage_group_switch})
	{
		$storage_group_uuid = $anvil->data->{storage_groups}{anvil_uuid}{$anvil_uuid}{storage_group_name}{$storage_group_switch}{storage_group_uuid};
		$storage_group_name = $storage_group_switch;
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			storage_group_uuid => $storage_group_uuid, 
			storage_group_name => $storage_group_name, 
		}});
	}
	elsif (exists $anvil->data->{storage_groups}{anvil_uuid}{$anvil_uuid}{storage_group_uuid}{$storage_group_switch})
	{
		$storage_group_uuid = $storage_group_switch;
		$storage_group_name = $anvil->data->{storage_groups}{anvil_uuid}{$anvil_uuid}{storage_group_uuid}{$storage_group_switch}{group_name};
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			storage_group_uuid => $storage_group_uuid, 
			storage_group_name => $storage_group_name, 
		}});
	}
	
	# Did we get a valid disk size?
	my $free_space = $anvil->data->{storage_groups}{anvil_uuid}{$anvil_uuid}{storage_group_uuid}{$storage_group_uuid}{free_space};
	my $add_size   = $anvil->data->{switches}{add};
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { add_size => $add_size }});
	if ($add_size =~ /^(\d+)%$/)
	{
		# This is valid
		my $percent = ".".$1;
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { percent => $percent }});
		
		$add_size = int($free_space * $percent);
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { add_size => $add_size }});
	}
	elsif ($add_size !~ /\d/)
	{
		# No digits, probably didn't set a value at all.
		print "\n[ Error ] - Please specify the size you would like to grow this disk by. The maximum size is: [".$anvil->Convert->bytes_to_human_readable({'bytes' => $free_space})."].\n";
		print $error_note."\n";
		$anvil->nice_exit({exit_code => 1});
	}
	elsif ($add_size !~ /^\d+$/)
	{
		# Size is not in bytes, try to convert it.
		my $bytes = $anvil->Convert->human_readable_to_bytes({
			debug => 2,
			size  => $add_size,
		});
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 'bytes' => $bytes }});
		if ($bytes =~ /^\d+$/)
		{
			$add_size = $bytes;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { add_size => $add_size }});
		}
		else
		{
			# Not a valid size.
			print "\n[ Error ] - The requested size: [".$add_size."] could not be interpreted.\n";
			print $error_note."\n";
			$anvil->nice_exit({exit_code => 1});
		}
	}
	
	# Still here? We're good to go.
	my $lv_command_size = 0;
	my $hr_size         = $anvil->Convert->bytes_to_human_readable({'bytes' => $add_size});
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { hr_size => $hr_size }});
	if ($add_size eq "100%")
	{
		# This is valid
		$add_size = "-l +100\%FREE";
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { add_size => $add_size }});
	}
	else
	{
		$hr_size  =~ s/\s+//g;
		$add_size =  "-L +".$hr_size;
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { add_size => $add_size }});
	}
	
	# What's the next free drive in the system, and what's the next free volume number?
	my $new_device_target = "";
	my $target_prefix     = "";
	my $disk_device_bus   = "";
	my $disk_cache        = "";
	my $disk_io_policy    = "";
	my $drive_letter      = "a";
	foreach my $device_target (sort {$a cmp $b} keys %{$anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{disk}{target}})
	{
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { device_target => $device_target }});
		if (not $disk_device_bus)
		{
			$target_prefix   = ($device_target =~ /^(\w+)\w$/)[0];
			$disk_device_bus = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{disk}{target}{$device_target}{device_bus};
			$disk_io_policy  = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{disk}{target}{$device_target}{driver}{io};
			$disk_cache      = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{disk}{target}{$device_target}{driver}{cache};
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				target_prefix   => $target_prefix, 
				disk_device_bus => $disk_device_bus,
				disk_io_policy  => $disk_io_policy, 
				disk_cache      => $disk_cache, 
			}});
			last;
		}
	}
	for (0..25)
	{
		my $test_device = $target_prefix.$drive_letter;
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { test_device => $test_device }});
		if (not exists $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{disk}{target}{$test_device})
		{
			# Found a free one.
			$new_device_target = $test_device;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { new_device_target => $new_device_target }});
			last;
		}
		$drive_letter++;
	}
	
	if (not $new_device_target)
	{
		print "\n[ Error ] - Failed to find a new target device name.\n";
		$anvil->nice_exit({exit_code => 1});
	}
	
	my $next_drbd_volume = "";
	foreach my $this_host (sort {$a cmp $b} keys %{$anvil->data->{drbd}{drbd_node}})
	{
		my $host_uuid       = $anvil->Get->host_uuid_from_name({debug => 2, host_name => $this_host});
		my $short_host_name = $anvil->data->{hosts}{host_uuid}{$host_uuid}{short_host_name};
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			's1:this_host'       => $this_host, 
			's2:host_uuid'       => $host_uuid, 
			's3:short_host_name' => $short_host_name, 
		}});
		
		if ($next_drbd_volume eq "")
		{
			my $test_drbd_volume = 0;
			for (0..100)
			{
				if (not $anvil->data->{new}{resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$test_drbd_volume}{device_path})
				{
					# This is free.
					$next_drbd_volume = $test_drbd_volume;
					$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { next_drbd_volume => $next_drbd_volume }});
					last;
				}
				$test_drbd_volume++;
				next;
			}
		}
		
		if ($next_drbd_volume eq "")
		{
			print "\n[ Error ] - Failed to find a new DRBD volume to use.\n";
			$anvil->nice_exit({exit_code => 1});
		}
	}
	
	### TODO: Make this work without the peer node being online.
	# The server is allowed to be running, but both nodes and any DR hosts this is replicating to
	# needs to be online.
	my $all_online = check_drbd_peer_access($anvil);
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { all_online => $all_online }});
	
	if (not $all_online)
	{
		print "\n[ Error ] - Adding a new disk requires all peers to be online.\n";
		foreach my $short_host_name (sort {$a cmp $b} keys %{$anvil->data->{peer}})
		{
			my $say_access = $anvil->data->{peer}{$short_host_name}{access_ip} ? "up." : "down!";
			print "          - Peer: [".$short_host_name."] is ".$say_access."\n";
		}
		$anvil->nice_exit({exit_code => 1});
	}
	
	# Still alive? Ask the user to confirm.
	print "- New drive target: [".$new_device_target."], size: [".$hr_size."], bus: [".$disk_device_bus."], cache: [".$disk_cache."], IO policy: [".$disk_io_policy."]\n";
	print "- Preparing to add a the drive: [".$drbd_resource."/".$next_drbd_volume."] using the storage group: [".$storage_group_name."]...\n";
	if (not $anvil->data->{switches}{confirm})
	{
		print $anvil->Words->string({key => "message_0021"})." ";
		my $answer = <STDIN>;
		chomp($answer);
		if ($answer !~ /^y/i)
		{
			print "Aborting.\n";
			$anvil->nice_exit({exit_code => 0});
		}
		
		# Test that we've lost access while waiting for the answer.
		my $all_online = check_drbd_peer_access($anvil);
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { all_online => $all_online }});
		
		if (not $all_online)
		{
			print "\n[ Error ] - It would appear that we've lost access to a peer while waiting for the answer.\n";
			foreach my $short_host_name (sort {$a cmp $b} keys %{$anvil->data->{peer}})
			{
				my $say_access = $anvil->data->{peer}{$short_host_name}{access_ip} ? "up." : "down!";
				print "          - Peer: [".$short_host_name."] is ".$say_access."\n";
			}
			$anvil->nice_exit({exit_code => 1});
		}
	}
	
	# Get the next free minor number
	my ($free_minor, undef) = $anvil->DRBD->get_next_resource({
		debug      => 2, 
		minor_only => 1,
		anvil_uuid => $anvil_uuid,
	});
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { free_minor => $free_minor }});
	
	# Create the new LVs
	foreach my $host_type ("node", "dr")
	{
		foreach my $short_host_name (sort {$a cmp $b} keys %{$anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}})
		{
			my $host_uuid        = $anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}{$short_host_name}{host_uuid};
			my $vg_name          = $anvil->data->{storage_groups}{anvil_uuid}{$anvil_uuid}{storage_group_uuid}{$storage_group_uuid}{host_uuid}{$host_uuid}{vg_name};
			my $vg_internal_uuid = $anvil->data->{storage_groups}{anvil_uuid}{$anvil_uuid}{storage_group_uuid}{$storage_group_uuid}{host_uuid}{$host_uuid}{vg_internal_uuid};
			my $new_lv_name      = $server_name."_".$next_drbd_volume;
			my $backing_disk     = "/dev/".$vg_name."/".$new_lv_name;
			my $shell_call       = "if [ -e '".$backing_disk."' ]; then echo 'LV: [".$backing_disk."] already exists.'; else ".$anvil->data->{path}{exe}{lvcreate}." ".$add_size." -n ".$new_lv_name." ".$vg_name."; fi;";
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				's1:short_host_name'  => $short_host_name,
				's2:host_uuid'        => $host_uuid, 
				's3:vg_name'          => $vg_name, 
				's4:vg_internal_uuid' => $vg_internal_uuid, 
				's5:new_lv_name'      => $new_lv_name, 
				's6:backing_disk'     => $backing_disk, 
				's7:shell_call'       => $shell_call, 
			}});
			
			# Record this for updating the DRBD resource.
			$anvil->data->{new_drbd}{$short_host_name}{resource}{$drbd_resource}{volume}{$next_drbd_volume}{minor}        = $free_minor;
			$anvil->data->{new_drbd}{$short_host_name}{resource}{$drbd_resource}{volume}{$next_drbd_volume}{backing_disk} = $backing_disk;
			$anvil->data->{new_drbd}{$short_host_name}{resource}{$drbd_resource}{volume}{$next_drbd_volume}{seen}         = 0;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				"new_drbd::${short_host_name}::resource::${drbd_resource}::volume::${next_drbd_volume}::minor"        => $anvil->data->{new_drbd}{$short_host_name}{resource}{$drbd_resource}{volume}{$next_drbd_volume}{minor},
				"new_drbd::${short_host_name}::resource::${drbd_resource}::volume::${next_drbd_volume}::backing_disk" => $anvil->data->{new_drbd}{$short_host_name}{resource}{$drbd_resource}{volume}{$next_drbd_volume}{backing_disk},
				"new_drbd::${short_host_name}::resource::${drbd_resource}::volume::${next_drbd_volume}::seen"         => $anvil->data->{new_drbd}{$short_host_name}{resource}{$drbd_resource}{volume}{$next_drbd_volume}{seen},
			}});
			
			# This lets us insert the new volume as needed.
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			}});
			if ($host_uuid eq $anvil->Get->host_uuid)
			{
				print " - Creating the new local LV: [".$backing_disk."]...";
				my ($output, $return_code) = $anvil->System->call({shell_call => $shell_call, source => $THIS_FILE, line => __LINE__});
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					output      => $output,
					return_code => $return_code, 
				}});
				if ($return_code)
				{
					print " Error!\n";
					print "[ FAILED ] - When trying to create the new local logical volume: [".$backing_disk."]\n";
					print "[ FAILED ] - using the command: [".$shell_call."]\n";
					print "[ FAILED ] - The return code: [".$return_code."] was received, expected '0'. Output, if any:\n";
					print "==========\n";
					print $output."\n";
					print "==========\n";
					print "The creation of the new replicatedd disk is incomplete, manual intervention is required!!\n";
					$anvil->nice_exit({exit_code => 1});
				}
				else
				{
					print " Done!\n";
				}
			}
			else
			{
				my $use_ip      = $anvil->data->{peer}{$short_host_name}{access}{ip};
				my $use_network = $anvil->data->{peer}{$short_host_name}{access}{network};
				print " - Creating the new LV on the peer: [".$short_host_name.":".$backing_disk."], via: [".$use_ip." (".$use_network.")]";
				my ($output, $error, $return_code) = $anvil->Remote->call({
					shell_call => $shell_call, 
					target     => $use_ip,
				});
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					output      => $output, 
					error       => $error,
					return_code => $return_code,
				}});
				if ($return_code)
				{
					print " Error!\n";
					print "[ FAILED ] - When trying to create the peer: [".$short_host_name."]'s logical volume: [".$backing_disk."]\n";
					print "[ FAILED ] - using the command: [".$shell_call."]\n";
					print "[ FAILED ] - The return code: [".$return_code."] was received, expected '0'. Output, if any:\n";
					print "==] STDOUT [========\n";
					print $output."\n";
					print "==] STDERR [========\n";
					print $error."\n";
					print "====================\n";
					print "The creation of the new replicated disk is incomplete, manual intervention is required!!\n";
					$anvil->nice_exit({exit_code => 1});
				}
				else
				{
					print " Done!\n";
				}
			}
		}
	}
	
	# Update the DRBD config file.
	my $new_res_file  = "";
	my $drbd_res_file = $anvil->data->{path}{directories}{drbd_resources}."/".$drbd_resource.".res";
	my $drbd_res_body = $anvil->Storage->read_file({file => $drbd_res_file});
	my $in_on_host    = "";
	my $in_volume     = "";
	foreach my $line (split /\n/, $drbd_res_body)
	{
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { line => $line }});
		if ($line =~ /on\s+(.*?)\s/)
		{
			$in_on_host = $1;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { line => $line }});
			
			$new_res_file .= $line."\n";
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 3, list => { new_res_file => $new_res_file }});
			next;
		}
		
		if (($in_on_host) && ($line =~ /volume\s+(\d+)\s/))
		{
			$in_volume = $1;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { in_volume => $in_volume }});
			
			$new_res_file .= $line."\n";
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 3, list => { new_res_file => $new_res_file }});
			
			$anvil->data->{new_drbd}{$in_on_host}{resource}{$drbd_resource}{volume}{$in_volume}{seen} = 0;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				"new_drbd::${in_on_host}::resource::${drbd_resource}::volume::${in_volume}::seen" => $anvil->data->{new_drbd}{$in_on_host}{resource}{$drbd_resource}{volume}{$in_volume}{seen},
			}});
			next;
		}
		
		if ($line =~ /}/)
		{
			if ($in_volume)
			{
				$in_volume = "";
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { in_volume => $in_volume }});
			}
			elsif ($in_on_host)
			{
				# This is where we insert the new volume, if we've not seen it yet.
				if (not $anvil->data->{new_drbd}{$in_on_host}{resource}{$drbd_resource}{volume}{$next_drbd_volume}{seen})
				{
					# Insert the line.
					$new_res_file .= $line."

                volume ".$next_drbd_volume." {
                        device    /dev/drbd_".$drbd_resource."_".$next_drbd_volume." minor ".$anvil->data->{new_drbd}{$short_host_name}{resource}{$drbd_resource}{volume}{$next_drbd_volume}{minor}.";
                        disk      ".$anvil->data->{new_drbd}{$in_on_host}{resource}{$drbd_resource}{volume}{$next_drbd_volume}{backing_disk}.";
                        meta-disk internal;
                }
";
					$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 3, list => { new_res_file => $new_res_file }});
					
					$anvil->data->{new_drbd}{$in_on_host}{resource}{$drbd_resource}{volume}{$next_drbd_volume}{seen} = 1;
					$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
						"new_drbd::${in_on_host}::resource::${drbd_resource}::volume::${in_volume}::seen" => $anvil->data->{new_drbd}{$in_on_host}{resource}{$drbd_resource}{volume}{$in_volume}{seen},
					}});
					next;
				}
			}
		}
		
		$new_res_file .= $line."\n";
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 3, list => { new_res_file => $new_res_file }});
	}
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { new_res_file => $new_res_file }});
	
	my $difference = diff \$drbd_res_body, \$new_res_file, { STYLE => 'Unified' };
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { difference => $difference }});
	
	# Write the file to a test file and verify it's sane,
	my $test_file = $anvil->data->{path}{directories}{temp}."/test-".$drbd_resource.".res";
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { test_file => $test_file }});
	my ($problem) = $anvil->Storage->write_file({
		debug     => 2,
		backup    => 0,
		overwrite => 1,
		file      => $test_file, 
		body      => $new_res_file,
		user      => "root", 
		group     => "root", 
		mode      => "0644",
	});
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { problem => $problem }});
	
	# Validate.
	print "- Testing the updated DRBD resource config file to ensure the new volumes are cromulent...";
	my $shell_call = $anvil->data->{path}{exe}{drbdadm}." --config-to-test ".$test_file." --config-to-exclude ".$drbd_res_file." sh-nop";
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { shell_call => $shell_call }});
	my ($output, $return_code) = $anvil->System->call({shell_call => $shell_call});
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		output      => $output,
		return_code => $return_code, 
	}});
	if ($return_code)
	{
		# Something went wrong.
		print " Failed!
[ Error ] - The new DRBD resource config appears to be invalid, which is likely a program error. The new 
[ Error ] - config was written to the test file: [".$test_file."].
[ Error ] - The test to confirm it was valid exited with the return code: [".$return_code."], expected '0'.
[ Error ] - The output, if anything, was:
====
".$output."
====
";
		$anvil->nice_exit({exit_code => 1});
	}
	print " Success!\n";
	
	# Remove the test file.
	unlink $test_file;
	
	# Backup the res file so we can tell the user where the current config was backed up to in 
	# case they need to restore it.
	print "- Writing out the updated DRBD config file.\n";
	my ($backup_file) = $anvil->Storage->backup({file => $drbd_res_file});
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { backup_file => $backup_file }});
	
	# Write out the new file.
	($problem) = $anvil->Storage->write_file({
		debug     => 2,
		backup    => 0,
		overwrite => 1,
		file      => $drbd_res_file, 
		body      => $new_res_file,
		user      => "root", 
		group     => "root", 
		mode      => "0644",
	});
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { backup_file => $backup_file }});
# 	
	# Copy this to our peers.
	print "- Copying the new resource file to out peers.\n";
	foreach my $host_type ("node", "dr")
	{
		foreach my $short_host_name (sort {$a cmp $b} keys %{$anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}})
		{
			my $host_uuid = $anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}{$short_host_name}{host_uuid};
			next if $host_uuid eq $anvil->Get->host_uuid;
			
			my $use_ip      =  $anvil->data->{peer}{$short_host_name}{access}{ip};
			my $destination =  "root\@".$use_ip.":".$anvil->data->{path}{directories}{drbd_resources}."/";
			   $destination =~ s/\/\//\//g;
			print " - Copying: [".$drbd_res_file."] to: [".$short_host_name.":".$destination."] via: [".$use_ip."]\n";
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				use_ip      => $use_ip,
				destination => $destination, 
			}});
			   
			my $failed = $anvil->Storage->rsync({
				debug       => 2, 
				destination => $destination,
				source      => $drbd_res_file,
			});
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { failed => $failed }});
			
			if ($failed)
			{
				print "
[ Error ] - There was a problem copying the new config file! Unable to proceed. 
[ Error ] - Manual intervention to complete the update is required!
";
				$anvil->nice_exit({exit_code => 1});
			}
		}
	}
	
	# Create the metadata.
	print "- Creating the replicated storage metadata on the new backing devices now.\n";
	foreach my $host_type ("node", "dr")
	{
		foreach my $short_host_name (sort {$a cmp $b} keys %{$anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}})
		{
			my $host_uuid  = $anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}{$short_host_name}{host_uuid};
			my $shell_call = $anvil->data->{path}{exe}{drbdadm}." --force create-md --max-peers=3 ".$drbd_resource."/".$next_drbd_volume;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				's1:short_host_name' => $short_host_name,
				's2:host_uuid'       => $host_uuid, 
				's3:shell_call'      => $shell_call, 
			}});
			
			# Create the metadata, but don't exit on failure in case the metadata was created in
			# a previous pass.
			if ($host_uuid eq $anvil->Get->host_uuid)
			{
				print " - Creating the meta-data on the new local volume: [".$next_drbd_volume."]...";
				my ($output, $return_code) = $anvil->System->call({shell_call => $shell_call, source => $THIS_FILE, line => __LINE__});
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					output      => $output,
					return_code => $return_code, 
				}});
				
				### Return codes
				# 0 == Success
				# 1 == ?
				# 3 == Configuration not found.
				if ($return_code)
				{
					print " Warning!\n";
					print "[ Warning ] - When trying to create the local meta-data on: [".$drbd_resource."/".$next_drbd_volume."]\n";
					print "[ Warning ] - using the command: [".$shell_call."]\n";
					print "[ Warning ] - The return code: [".$return_code."] was received, expected '0'. Output, if any:\n";
					print "==========\n";
					print $output."\n";
					print "==========\n";
					print "We will try to proceed anyway.\n";
				}
				else
				{
					print " Done!\n";
				}
			}
			else
			{
				my $use_ip      = $anvil->data->{peer}{$short_host_name}{access}{ip};
				my $use_network = $anvil->data->{peer}{$short_host_name}{access}{network};
				print " - Creating the meta-data on the peer: [".$short_host_name.":".$drbd_resource."/".$next_drbd_volume."], via: [".$use_ip." (".$use_network.")]";
				my ($output, $error, $return_code) = $anvil->Remote->call({
					shell_call => $shell_call, 
					target     => $use_ip,
				});
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					output      => $output, 
					error       => $error,
					return_code => $return_code,
				}});
				if ($return_code)
				{
					print " Warning!\n";
					print "[ Warning ] - When trying to create the peer: [".$short_host_name."]'s meta-data on: [".$drbd_resource."/".$next_drbd_volume."]\n";
					print "[ Warning ] - using the command: [".$shell_call."]\n";
					print "[ Warning ] - The return code: [".$return_code."] was received, expected '0'. Output, if any:\n";
					print "==] STDOUT [========\n";
					print $output."\n";
					print "==] STDERR [========\n";
					print $error."\n";
					print "====================\n";
					print "We will try to proceed anyway.\n";
				}
				else
				{
					print " Done!\n";
				}
			}
		}
	}
	
	### NOTE: The call to 'drbdadm adjust <res>' hangs, hard, until the same command is run on the peers.
	###       To deal with this, we register jobs to run 'anvil-special-operations' on the peers, then we
	###       call adjust here. 
	# Adjust to start/connect.
	foreach my $host_type ("node", "dr")
	{
		foreach my $short_host_name (sort {$a cmp $b} keys %{$anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}})
		{
			my $host_uuid  = $anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}{$short_host_name}{host_uuid};
			my $shell_call = $anvil->data->{path}{exe}{'anvil-special-operations'}." --task refresh-drbd-resource --resource ".$drbd_resource.$anvil->Log->switches;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				's1:short_host_name' => $short_host_name,
				's2:host_uuid'       => $host_uuid, 
				's3:shell_call'      => $shell_call, 
			}});
			next if $host_uuid eq $anvil->Get->host_uuid;
			
			my ($job_uuid) = $anvil->Database->insert_or_update_jobs({
				debug           => 2, 
				job_command     => $shell_call, 
				job_data        => "adjust=".$drbd_resource, 
				job_name        => "server::add_disk::rescan", 
				job_title       => "job_0465", 
				job_description => "job_0466", 
				job_progress    => 0,
				job_host_uuid   => $host_uuid, 
			});
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { job_uuid => $job_uuid }});
			
			print "- Registered a job with job UUID: [".$job_uuid."] to reload the resource config on the host: [".$short_host_name."].\n";
		}
	}
	
	print "- Adjusting the local resource: [".$drbd_resource."] to pick up the new config.\n";
	print "[ NOTE ] - If this hangs, make sure 'anvil-daemon' is running on the peers.\n";
	$shell_call = $anvil->data->{path}{exe}{drbdadm}." adjust ".$drbd_resource;
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { shell_call => $shell_call }});
	($output, $return_code) = $anvil->System->call({
		debug      => 2,
		background => 1,
		shell_call => $shell_call,
	});
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		output      => $output,
		return_code => $return_code, 
	}});
	
	# Find which node is currently Primary and use that host to force primary to start sync. If none, 
	# force here.
	print "- Waiting for all peers to connect the new volume...";
	my $waiting    = 1;
	my $wait_until = time + 60;
	while ($waiting)
	{
		$anvil->DRBD->get_status({debug => 2});
		my $peers_connected = 1;
		my $disks_ready     = 0;
		foreach my $this_host_name (sort {$a cmp $b} keys %{$anvil->data->{peers}})
		{
			my $host_uuid        = $anvil->data->{peers}{$this_host_name}{host_uuid};
			my $connection_state = $anvil->data->{drbd}{status}{$short_host_name}{resource}{$drbd_resource}{connection}{$this_host_name}{'connection-state'};
			my $node_id          = $anvil->data->{drbd}{status}{$short_host_name}{resource}{$drbd_resource}{connection}{$this_host_name}{'peer-node-id'};
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				's1:this_host_name'   => $this_host_name, 
				's2:host_uuid'        => $host_uuid, 
				's3:connection_state' => $connection_state, 
				's4:node_id'          => $node_id,
			}});
			if (lc($connection_state) ne "connected")
			{
				$peers_connected = 0;
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { peers_connected => $peers_connected }});
			}
		}
		
		if ($peers_connected)
		{
			# Make sure all disks are attached.
			$disks_ready                                        = 1;
			$anvil->data->{peers}{$short_host_name}{disk_state} = $anvil->data->{drbd}{status}{$short_host_name}{resource}{$drbd_resource}{devices}{volume}{$next_drbd_volume}{'disk-state'};
			$anvil->data->{peers}{$short_host_name}{role}       = $anvil->data->{drbd}{status}{$short_host_name}{resource}{$drbd_resource}{role};
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				"peers::${short_host_name}::disk_state" => $anvil->data->{peers}{$short_host_name}{disk_state},
			}});
			foreach my $peer_name (sort {$a cmp $b} keys %{$anvil->data->{drbd}{status}{$short_host_name}{resource}{$drbd_resource}{connection}})
			{
				my $peer_disk_state   = $anvil->data->{drbd}{status}{$short_host_name}{resource}{$drbd_resource}{connection}{$peer_name}{volume}{$next_drbd_volume}{'peer-disk-state'};
				my $replication_state = $anvil->data->{drbd}{status}{$short_host_name}{resource}{$drbd_resource}{connection}{$peer_name}{volume}{$next_drbd_volume}{'replication-state'};
				my $role              = $anvil->data->{drbd}{status}{$short_host_name}{resource}{$drbd_resource}{connection}{$peer_name}{'peer-role'};
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					's1:peer_name'         => $peer_name, 
					's2:peer_disk_state'   => $peer_disk_state, 
					's3:replication_state' => $replication_state,
					's4:role'              => $role, 
				}});
				if (lc($replication_state) ne "established")
				{
					$disks_ready = 0;
					$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { peers_connected => $peers_connected }});
				}
				
				$anvil->data->{peers}{$peer_name}{disk_state} = $peer_disk_state;
				$anvil->data->{peers}{$peer_name}{role}       = $role;
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					"peers::${peer_name}::disk_state" => $anvil->data->{peers}{$peer_name}{disk_state},
				}});
			}
		}
		
		if ($disks_ready)
		{
			$waiting = 0;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { waiting => $waiting }});
		}
		else
		{
			if (time > $wait_until)
			{
				print " Failed!\n[ Error ] - The peers did not connect in the expected period of time.\n";
				$anvil->nice_exit({exit_code => 1});
			}
			sleep 2;
		}
	}
	print " Done!\n";
	
	print "- Peers are connected! Checking if the new volume requires initial sync.\n";
	my $all_inconsistent = 1;
	my $primary_on_host  = "";
	foreach my $peer_name (sort {$a cmp $b} keys %{$anvil->data->{peers}})
	{
		my $disk_state = $anvil->data->{peers}{$peer_name}{disk_state};
		my $role       = $anvil->data->{peers}{$peer_name}{role};
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			peer_name  => $peer_name, 
			disk_state => $disk_state,
			role       => $role, 
		}});
		if (lc($disk_state) ne "inconsistent")
		{
			$all_inconsistent = 0;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { all_inconsistent => $all_inconsistent }});
		}
		if (lc($role) eq "primary")
		{
			$primary_on_host = $peer_name;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { primary_on_host => $primary_on_host }});
		}
	}
	
	if ($all_inconsistent)
	{
		print "- Initial sync required!\n";
		my $shell_call = $anvil->data->{path}{exe}{drbdadm}." primary ".$drbd_resource." --force";
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { shell_call => $shell_call }});
		
		# Which node should be forced primary?
		if (not $primary_on_host)
		{
			# We'll make it primary.
			$primary_on_host = $short_host_name;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { primary_on_host => $primary_on_host }});
		}
		
		my $primary_on_host_uuid = $anvil->Get->host_uuid_from_name({debug => 2, host_name => $primary_on_host});
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { primary_on_host_uuid => $primary_on_host_uuid }});
		if ($primary_on_host_uuid eq $anvil->Get->host_uuid)
		{
			print "- Forcing primary locally... ";
			my ($output, $return_code) = $anvil->System->call({shell_call => $shell_call});
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				output      => $output,
				return_code => $return_code,
			}});
			# Return code of '0' is success.
			if ($return_code)
			{
				print "Failed!
[ Error ] - There was a problem trying to force the new volume: [".$drbd_resource."/".$next_drbd_volume."] to Primary.
[ Error ] - Attempted this using the shell call: [".$shell_call."].
[ Error ] - Expected the return code '0' but got: [".$return_code."]. The output, if any, was:
==========
".$output."
==========
[ Error ] - Once corrected, please manually add the new volume to the server.
";
				$anvil->nice_exit({exit_code => 1});
			}
			
			# Now demote it again.
			$shell_call = $anvil->data->{path}{exe}{drbdadm}." secondary ".$drbd_resource;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { shell_call => $shell_call }});
			
			($output, $return_code) = $anvil->System->call({shell_call => $shell_call});
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				output      => $output,
				return_code => $return_code,
			}});
			print "Success!\n";
		}
		else
		{
			my $use_ip      = $anvil->data->{peer}{$short_host_name}{access}{ip};
			my $use_network = $anvil->data->{peer}{$short_host_name}{access}{network};
			print " - The resource is primary on the peer: [".$short_host_name."], forcing primary there via: [".$use_ip." (".$use_network.")]";
			my ($output, $error, $return_code) = $anvil->Remote->call({
				shell_call => $shell_call, 
				target     => $use_ip,
			});
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				output      => $output, 
				error       => $error,
				return_code => $return_code,
			}});
			if ($return_code)
			{
				print "Failed!
[ Error ] - There was a problem trying to force the new volume: [".$drbd_resource."/".$next_drbd_volume."] to Primary.
[ Error ] - Attempted this using the shell call: [".$shell_call."].
[ Error ] - Expected the return code '0' but got: [".$return_code."]. The output, if any, was:
==========
".$output."
==========
[ Error ] - Once corrected, please manually add the new volume to the server.
";
				$anvil->nice_exit({exit_code => 1});
			}
			
			# Now demote it again.
			$shell_call = $anvil->data->{path}{exe}{drbdadm}." secondary ".$drbd_resource;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { shell_call => $shell_call }});
			($output, $error, $return_code) = $anvil->Remote->call({
				shell_call => $shell_call, 
				target     => $use_ip,
			});
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				output      => $output, 
				error       => $error,
				return_code => $return_code,
			}});
			print "Success!\n";
		}
	}
	else
	{
		print "Initial sync does not appear to be required.\n";
	}

=cut
	my $startup_needed = 1;
	my $local_role     = defined $anvil->data->{drbd}{status}{$short_host_name}{resource}{$drbd_resource}{role} ? $anvil->data->{drbd}{status}{$short_host_name}{resource}{$drbd_resource}{role} : "";
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { local_role => $local_role }});
	
	# Create the DRBD metadata. For this, we don't fail.
	foreach my $host_type ("node", "dr")
	{
		foreach my $short_host_name (sort {$a cmp $b} keys %{$anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}})
		{
			my $host_uuid  = $anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}{$short_host_name}{host_uuid};
			my $shell_call = $anvil->data->{path}{exe}{drbdadm}." --force create-md --max-peers=3 ".$drbd_resource."/".$next_drbd_volume;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				's1:short_host_name' => $short_host_name,
				's2:host_uuid'       => $host_uuid, 
				's7:shell_call'      => $shell_call, 
			}});
			if ($host_uuid eq $anvil->Get->host_uuid)
			{
				print " - Creating the new local LV: [".$backing_disk."]...";
				my ($output, $return_code) = $anvil->System->call({shell_call => $shell_call, source => $THIS_FILE, line => __LINE__});
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					output      => $output,
					return_code => $return_code, 
				}});
				if ($return_code)
				{
					print " Error!\n";
					print "[ FAILED ] - When trying to create the new local logical volume: [".$backing_disk."]\n";
					print "[ FAILED ] - using the command: [".$shell_call."]\n";
					print "[ FAILED ] - The return code: [".$return_code."] was received, expected '0'. Output, if any:\n";
					print "==========\n";
					print $output."\n";
					print "==========\n";
					print "The creation of the new replicatedd disk is incomplete, manual intervention is required!!\n";
					$anvil->nice_exit({exit_code => 1});
				}
				else
				{
					print " Done!\n";
				}
			}
			else
			{
				my $use_ip      = $anvil->data->{peer}{$short_host_name}{access}{ip};
				my $use_network = $anvil->data->{peer}{$short_host_name}{access}{network};
				print " - Creating the new LV on the peer: [".$short_host_name.":".$backing_disk."], via: [".$use_ip." (".$use_network.")]";
				my ($output, $error, $return_code) = $anvil->Remote->call({
					shell_call => $shell_call, 
					target     => $use_ip,
				});
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					output      => $output, 
					error       => $error,
					return_code => $return_code,
				}});
				if ($return_code)
				{
					print " Error!\n";
					print "[ FAILED ] - When trying to create the peer's logical volume: [".$backing_disk."]\n";
					print "[ FAILED ] - using the command: [".$shell_call."]\n";
					print "[ FAILED ] - The return code: [".$return_code."] was received, expected '0'. Output, if any:\n";
					print "==] STDOUT [========\n";
					print $output."\n";
					print "==] STDERR [========\n";
					print $error."\n";
					print "====================\n";
					print "The creation of the new replicated disk is incomplete, manual intervention is required!!\n";
					$anvil->nice_exit({exit_code => 1});
				}
				else
				{
					print " Done!\n";
				}
			}
		}
	}
=cut
	
	return(0);
}

sub manage_disk_grow
{
	my ($anvil, $drbd_resource, $drbd_volume, $max_free_space) = @_;
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		's1:drbd_resource'  => $drbd_resource,
		's2:drbd_volume'    => $drbd_volume, 
		's3:max_free_space' => $max_free_space, 
	}});
	
	my $anvil_uuid      = defined $anvil->data->{switches}{anvil_uuid} ? $anvil->data->{switches}{anvil_uuid} : $anvil->Cluster->get_anvil_uuid();
	my $short_host_name = $anvil->Get->short_host_name;
	my $server_name     = $anvil->data->{switches}{server_name};
	my $from_source     = get_definition_source($anvil);
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		anvil_uuid      => $anvil_uuid, 
		short_host_name => $short_host_name,
		server_name     => $server_name, 
		from_source     => $from_source, 
	}});
	
	# Are they asking for an available amount of space?
	my $error_note = q|
[ Note ]  - The size can be in percent, ie: '50%' or '100%', a number in bytes, or a human-readable size.
          - Human readable sizes must NOT have a space between the number and letter suffix. Also, base2 
          - vs base10 notation! Ie: '1GiB' = 1,073,741,824 bytes', '1GB' == '1,000,000,000 bytes'. A single
          - letter used to denote size will be interpreted as base2. ie: '1G == 1GiB'.
|;

	my $add_size = $anvil->data->{switches}{grow};
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { add_size => $add_size }});
	if ($add_size =~ /^(\d+)%$/)
	{
		# This is valid
		my $percent = ".".$1;
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { percent => $percent }});
		
		$add_size = int($max_free_space * $percent);
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { add_size => $add_size }});
	}
	elsif ($add_size !~ /\d/)
	{
		# No digits, probably didn't set a value at all.
		print "\n[ Error ] - Please specify the size you would like to grow this disk by. The maximum size is: [".$anvil->Convert->bytes_to_human_readable({'bytes' => $max_free_space})."].\n";
		print $error_note."\n";
		$anvil->nice_exit({exit_code => 1});
	}
	elsif ($add_size !~ /^\d+$/)
	{
		# Size is not in bytes, try to convert it.
		my $bytes = $anvil->Convert->human_readable_to_bytes({
			debug => 2,
			size  => $add_size,
		});
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 'bytes' => $bytes }});
		if ($bytes =~ /^\d+$/)
		{
			$add_size = $bytes;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { add_size => $add_size }});
		}
		else
		{
			# Not a valid size.
			print "\n[ Error ] - The requested size: [".$add_size."] could not be interpreted.\n";
			print $error_note."\n";
			$anvil->nice_exit({exit_code => 1});
		}
	}
	
	# Make sure they're asking for a reasonable size
	if ($add_size < 4194304)
	{
		# Must be a typo, this is less than the size of a single extent.
		print "\n[ Error ] - The requested size: [".$anvil->Convert->bytes_to_human_readable({'bytes' => $add_size})."] is too small, it's less than an single extent.\n";
		print $error_note."\n";
		$anvil->nice_exit({exit_code => 1});
	}
	elsif ($add_size > $max_free_space)
	{
		# Not enough space.
		print "\n[ Error ] - The requested size: [".$anvil->Convert->bytes_to_human_readable({'bytes' => $add_size})."] is too large. The available size is: [".$anvil->Convert->bytes_to_human_readable({'bytes' => $max_free_space})."]\n";
		print $error_note."\n";
		$anvil->nice_exit({exit_code => 1});
	}
	
	### TODO: Make this work without the peer node being online.
	# The server is allowed to be running, but both nodes and any DR hosts this is replicating to
	# needs to be online.
	my $all_online = check_drbd_peer_access($anvil);
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { all_online => $all_online }});
	
	if (not $all_online)
	{
		print "\n[ Error ] - Growing the storage requires all peers to be online.\n";
		foreach my $short_host_name (sort {$a cmp $b} keys %{$anvil->data->{peer}})
		{
			my $say_access = $anvil->data->{peer}{$short_host_name}{access_ip} ? "up." : "down!";
			print "          - Peer: [".$short_host_name."] is ".$say_access."\n";
		}
		$anvil->nice_exit({exit_code => 1});
	}
	
	# Still here? We're good to go.
	my $lv_command_size = 0;
	my $hr_size         = $anvil->Convert->bytes_to_human_readable({'bytes' => $add_size});
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { hr_size => $hr_size }});
	if ($add_size eq "100%")
	{
		# This is valid
		$add_size = "-l +100\%FREE";
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { add_size => $add_size }});
	}
	else
	{
		$hr_size  =~ s/\s+//g;
		$add_size =  "-L +".$hr_size;
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { add_size => $add_size }});
	}
	
	print "- Preparing to grow the storage by: [".$hr_size."]...\n";
	if (not $anvil->data->{switches}{confirm})
	{
		print $anvil->Words->string({key => "message_0021"})." ";
		my $answer = <STDIN>;
		chomp($answer);
		if ($answer !~ /^y/i)
		{
			print "Aborting.\n";
			$anvil->nice_exit({exit_code => 0});
		}
		
		# Test that we've lost access while waiting for the answer.
		my $all_online = check_drbd_peer_access($anvil);
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { all_online => $all_online }});
		
		if (not $all_online)
		{
			print "\n[ Error ] - It would appear that we've lost access to a peer while waiting for the answer.\n";
			foreach my $short_host_name (sort {$a cmp $b} keys %{$anvil->data->{peer}})
			{
				my $say_access = $anvil->data->{peer}{$short_host_name}{access_ip} ? "up." : "down!";
				print "          - Peer: [".$short_host_name."] is ".$say_access."\n";
			}
			$anvil->nice_exit({exit_code => 1});
		}
	}
	
	foreach my $host_type ("node", "dr")
	{
		foreach my $short_host_name (sort {$a cmp $b} keys %{$anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}})
		{
			my $host_uuid    = $anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}{$short_host_name}{host_uuid};
			my $backing_disk = $anvil->data->{new}{resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$drbd_volume}{backing_disk};
			my $shell_call   = $anvil->data->{path}{exe}{lvextend}." ".$add_size." ".$backing_disk;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				's1:short_host_name' => $short_host_name,
				's2:host_uuid'       => $host_uuid, 
				's3:backing_disk'    => $backing_disk, 
				's4:shell_call'      => $shell_call, 
			}});
			if ($host_uuid eq $anvil->Get->host_uuid)
			{
				print " - Extending local LV: [".$backing_disk."]...";
				my ($output, $return_code) = $anvil->System->call({shell_call => $shell_call, source => $THIS_FILE, line => __LINE__});
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					output      => $output,
					return_code => $return_code, 
				}});
				if ($return_code)
				{
					print " Error!\n";
					print "[ FAILED ] - When trying to grow the local logical volume: [".$backing_disk."]\n";
					print "[ FAILED ] - using the command: [".$shell_call."]\n";
					print "[ FAILED ] - The return code: [".$return_code."] was received, expected '0'. Output, if any:\n";
					print "==========\n";
					print $output."\n";
					print "==========\n";
					print "The extension of the resource is incomplete, manual intervention is required!!\n";
					print "[ Warning ] - Do NOT re-run this command! The backing devices may not have mis-matched sized!\n";
					$anvil->nice_exit({exit_code => 1});
				}
				else
				{
					print " Done!\n";
				}
			}
			else
			{
				my $use_ip      = $anvil->data->{peer}{$short_host_name}{access}{ip};
				my $use_network = $anvil->data->{peer}{$short_host_name}{access}{network};
				print " - Extending peer: [".$short_host_name.":".$backing_disk."], via: [".$use_ip." (".$use_network.")]";
				my ($output, $error, $return_code) = $anvil->Remote->call({
					shell_call => $shell_call, 
					target     => $use_ip,
				});
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					output      => $output, 
					error       => $error,
					return_code => $return_code,
				}});
				if ($return_code)
				{
					print " Error!\n";
					print "[ FAILED ] - When trying to grow the peer's logical volume: [".$backing_disk."]\n";
					print "[ FAILED ] - using the command: [".$shell_call."]\n";
					print "[ FAILED ] - The return code: [".$return_code."] was received, expected '0'. Output, if any:\n";
					print "==] STDOUT [========\n";
					print $output."\n";
					print "==] STDERR [========\n";
					print $error."\n";
					print "====================\n";
					print "The extension of the resource is incomplete, manual intervention is required!!\n";
					print "[ Warning ] - Do NOT re-run this command! The backing devices may not have mis-matched sized!\n";
					$anvil->nice_exit({exit_code => 1});
				}
				else
				{
					print " Done!\n";
				}
			}
		}
	}
	
	# Locally, we'll call DRBD to resize.
	print "- Extending backing devices complete. Now extending DRBD resource/volume... ";
	my $shell_call = $anvil->data->{path}{exe}{drbdadm}." resize ".$drbd_resource."/".$drbd_volume;
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { shell_call => $shell_call }});
	
	my ($output, $return_code) = $anvil->System->call({shell_call => $shell_call, source => $THIS_FILE, line => __LINE__});
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		output      => $output,
		return_code => $return_code, 
	}});
	if ($return_code)
	{
		print " Error!\n";
		print "[ FAILED ] - When trying to grow the DRBD device: [".$drbd_resource."/".$drbd_volume."]\n";
		print "[ FAILED ] - using the command: [".$shell_call."]\n";
		print "[ FAILED ] - The return code: [".$return_code."] was received, expected '0'. Output, if any:\n";
		print "==========\n";
		print $output."\n";
		print "==========\n";
		print "The extension of the resource is incomplete, manual intervention is required!!\n";
		print "[ Note ] - All backing devices have been grown. Manually resolving the drbd grow\n";
		print "[ Note ] - error should complete the drive expansion!\n";
		$anvil->nice_exit({exit_code => 1});
	}
	else
	{
		print " Done!\n";
	}
	
	# Call scan-lvm and scan-drbd to make sure the databases are updated.
	print "- Calling scancore agents to ensure the database has the new storage config recorded.\n";
	foreach my $agent ("scan-drbd", "scan-lvm")
	{
		$anvil->Log->entry({source => $THIS_FILE, line => __LINE__, level => 1, key => "log_0740", variables => { agent => $agent }});
		
		my $shell_call = $anvil->data->{path}{directories}{scan_agents}."/".$agent."/".$agent.$anvil->Log->switches();
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { shell_call => $shell_call }});
		foreach my $host_type ("node", "dr")
		{
			foreach my $short_host_name (sort {$a cmp $b} keys %{$anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}})
			{
				my $host_uuid = $anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}{$short_host_name}{host_uuid};
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					's1:short_host_name' => $short_host_name,
					's2:host_uuid'       => $host_uuid, 
				}});
				if ($host_uuid eq $anvil->Get->host_uuid)
				{
					print " - Running scan agent: [".$agent."] locally...";
					my ($output, $return_code) = $anvil->System->call({shell_call => $shell_call, source => $THIS_FILE, line => __LINE__});
					$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
						output      => $output,
						return_code => $return_code, 
					}});
					print " Done!\n";
				}
				else
				{
					my $use_ip      = $anvil->data->{peer}{$short_host_name}{access}{ip};
					my $use_network = $anvil->data->{peer}{$short_host_name}{access}{network};
					print " - Running scan agent: [".$agent."] on: [".$short_host_name."] via: [".$use_ip." (".$use_network.")]...";
					my ($output, $error, $return_code) = $anvil->Remote->call({
						shell_call => $shell_call, 
						target     => $use_ip,
					});
					$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
						output      => $output, 
						error       => $error,
						return_code => $return_code,
					}});
					print " Done!\n";
				}
			}
		}
	}
	
	print "[ Success ] - Expansion is complete!\n";
	print "[ Note ]    - Depending on your OS, you may need to power the server off, and then power it back on\n";
	print "[ Note ]    - for the new space to be visible. Typically, powering off the server from the guest OS\n";
	print "[ Note ]    - and waiting for the Anvil! to boot it back up will do the job nicely.\n";
	
	return(0);
}

sub manage_optical
{
	my ($anvil) = @_;
	
	my $short_host_name = $anvil->Get->short_host_name;
	my $server_name     = $anvil->data->{switches}{server_name};
	my $from_source     = get_definition_source($anvil);
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		short_host_name => $short_host_name,
		server_name     => $server_name, 
		from_source     => $from_source, 
	}});
	
	if (not $anvil->data->{switches}{optical})
	{
		# If there's only one optical drive, select it automatically
		my $count = keys %{$anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{cdrom}{target}};
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { count => $count }});
		if ($count == 1)
		{
			foreach my $device_target (sort {$a cmp $b} keys %{$anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{cdrom}{target}})
			{
				$anvil->data->{switches}{optical} = $device_target;
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					"switches::drive" => $anvil->data->{switches}{optical},
				}});
				last;
			}
		}
		
		if (not $anvil->data->{switches}{optical})
		{
			# Can't proceed.
			print "\n[ Error ] - Please indicate the optical drive to work with using '--optical <target_device>'.\n\n";
			show_server_details($anvil);
			$anvil->nice_exit({exit_code => 1});
		}
	}
	my $device_target = $anvil->data->{switches}{optical};
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { device_target => $device_target }});
	
	if ($anvil->data->{switches}{optical} eq "#!SET!#")
	{
		# User didn't specify a device.
		show_server_details($anvil);
		print "\n[ Error ] - Please specify the optical disk target you want to work on.\n";
		$anvil->nice_exit({exit_code => 1});
	}
	elsif (not exists $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{cdrom}{target}{$device_target})
	{
		# Invalid device target
		show_server_details($anvil);
		print "\n[ Error ] - The optical device target: [".$device_target."] wasn't found.\n";
		$anvil->nice_exit({exit_code => 1});
	}
	
	my $eject_first        = 0;
	my $alias              = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{cdrom}{target}{$device_target}{alias};
	my $boot_order         = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{cdrom}{target}{$device_target}{boot_order};
	my $say_boot           = $boot_order eq "99" ? "--" : sprintf("%02d", $boot_order);
	my $type               = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{cdrom}{target}{$device_target}{type};
	my $address_type       = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{cdrom}{target}{$device_target}{address}{type};
	my $address_bus        = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{cdrom}{target}{$device_target}{address}{bus};
	my $driver_name        = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{cdrom}{target}{$device_target}{driver}{name};
	my $device_bus         = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{cdrom}{target}{$device_target}{device_bus};
	my $driver_type        = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{cdrom}{target}{$device_target}{driver}{type};
	my $address_controller = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{cdrom}{target}{$device_target}{address}{controller};
	my $address_unit       = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{cdrom}{target}{$device_target}{address}{unit};
	my $address_target     = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{cdrom}{target}{$device_target}{address}{target};
	my $device_path        = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{cdrom}{target}{$device_target}{path};
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		's01:device_target'      => $device_target,
		's02:alias'              => $alias, 
		's03:boot_order'         => $boot_order,
		's04:say_boot'           => $say_boot, 
		's05:type'               => $type, 
		's06:address_type'       => $address_type, 
		's07:address_bus'        => $address_bus, 
		's08:driver_name'        => $driver_name, 
		's09:device_bus'         => $device_bus, 
		's10:driver_type'        => $driver_type, 
		's11:address_controller' => $address_controller,
		's12:address_unit'       => $address_unit, 
		's13:address_target'     => $address_target, 
		's14:device_path'        => $device_path, 
	}});
	
	# Without a --source, the result is an eject.
	my $shell_call = $anvil->data->{path}{exe}{setsid}." --wait ".$anvil->data->{path}{exe}{virsh}." change-media ".$server_name." --path ".$device_target." --update --live --config";
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { shell_call => $shell_call }});
	if ($anvil->data->{switches}{insert})
	{
		# Make sure the new target exists.
		my $iso = $anvil->data->{switches}{insert};
		if (not -f $iso)
		{
			print "[ Error ] - The target: [".$iso."] doesn't exist, can't insert it into the optical drive.\n";
			update_definition($anvil, "undefine");
			$anvil->nice_exit({exit_code => 1});
		}
		else
		{
			$shell_call .= " --source ".$anvil->data->{switches}{insert};
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { shell_call => $shell_call }});
		}
	}
	
	# If the server is running, update the on-disk and in-DB definition.
	print "Defining the server: [".$server_name."] to prepare for 'virsh' modification of the server.\n";
	update_definition($anvil, "define");
	
	# Now we can modify the server using virsh.
	if ($anvil->data->{switches}{insert})
	{
		print "- Inserting: [".$anvil->data->{switches}{insert}."] into the drive: [".$device_target."].\n";
	}
	elsif ($anvil->data->{switches}{eject})
	{
		print "- Ejecting: [".$device_path."] from: [".$device_target."].\n";
	}
	else
	{
		# Show the ISO in the drive.
		if ($device_path)
		{
			print "- Drive: [".$device_target."] has the disc image: [".$device_path."] inserted currently.\n";
			print "- Use '--eject' to eject the disc.\n";
			print "- Use '--insert /mnt/shared/files/<file>' to replace it with a different disc image.\n";
		}
		else
		{
			print "- Drive: [".$device_target."] currently has no disc image inserted.\n";
			print "- Use '--insert /mnt/shared/files/<file>' to insert a disc image.\n";
		}
		$anvil->nice_exit({exit_code => 0});
	}
	my ($output, $return_code) = $anvil->System->call({debug => 2, shell_call => $shell_call});
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		's1:output'      => $output,
		's2:return_code' => $return_code, 
	}});
	print "'virsh' Output: [".$output."]\n";
	
	print "Updating the stored definition and undefining the server now:\n";
	update_definition($anvil, "undefine");
	print "Done!\n";
	
	return(0);
}

sub get_definition_source
{
	my ($anvil) = @_;
	
	my $short_host_name  = $anvil->Get->short_host_name;
	my $server_name      = $anvil->data->{switches}{server_name};
	my $server_uuid      = $anvil->data->{switches}{server_uuid};
	my $server_state     = $anvil->data->{servers}{server_uuid}{$server_uuid}{server_state};
	my $server_host_uuid = $anvil->data->{servers}{server_uuid}{$server_uuid}{server_host_uuid};
	my $from_source      = "";
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		short_host_name => $short_host_name,
		server_name     => $server_name, 
		server_uuid     => $server_uuid, 
		server_state    => $server_state, 
		from_source     => $from_source, 
	}});
	
	$anvil->data->{server}{$short_host_name}{$server_name}{from_virsh} = "" if not exists $anvil->data->{server}{$short_host_name}{$server_name}{from_virsh};
	$anvil->data->{server}{$short_host_name}{$server_name}{from_disk}  = "" if not exists $anvil->data->{server}{$short_host_name}{$server_name}{from_disk};
	$anvil->data->{server}{$short_host_name}{$server_name}{from_db}    = "" if not exists $anvil->data->{server}{$short_host_name}{$server_name}{from_db};
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		"server::${short_host_name}::${server_name}::from_virsh" => $anvil->data->{server}{$short_host_name}{$server_name}{from_virsh},
		"server::${short_host_name}::${server_name}::from_disk"  => $anvil->data->{server}{$short_host_name}{$server_name}{from_disk},
		"server::${short_host_name}::${server_name}::from_db"    => $anvil->data->{server}{$short_host_name}{$server_name}{from_db},
	}});
	
	if (($server_state eq "running")                    && 
	    ($server_host_uuid eq $anvil->Get->host_uuid()) && 
	    (exists $anvil->data->{server}{$short_host_name}{$server_name}{from_virsh}))
	{
		$from_source = "from_virsh";
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { from_source => $from_source }});
	}
	elsif (exists $anvil->data->{server}{$short_host_name}{$server_name}{from_disk})
	{
		$from_source = "from_disk";
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { from_source => $from_source }});
	}
	else
	{
		$from_source = "from_db";
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { from_source => $from_source }});
	}

	return($from_source);
}

sub show_server_details
{
	my ($anvil) = @_;
	
	my $short_host_name = $anvil->Get->short_host_name;
	my $host_uuid       = $anvil->Get->host_uuid;
	my $server_name     = $anvil->data->{switches}{server_name};
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		's1:short_host_name' => $short_host_name,
		's2:host_uuid'       => $host_uuid,
		's2:server_name'     => $server_name, 
	}});
	
	# Load storage data
	my $drbd_resource = load_storage($anvil);
	
	my $from_source = get_definition_source($anvil);
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { from_source => $from_source }});
	foreach my $device ("disk", "cdrom")
	{
		if ($device eq "disk")
		{
			print "\nDisk Drives:\n";
		}
		else
		{
			print "\nOptical Drives:\n";
		}
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { device => $device }});
		next if $device ne "cdrom" &&  $device ne "disk";
		foreach my $device_target (sort {$a cmp $b} keys %{$anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}})
		{
			my $alias        = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{alias};
			my $boot_order   = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{boot_order};
			my $say_boot     = $boot_order eq "99" ? "--" : sprintf("%02d", $boot_order);
			my $type         = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{type};
			my $address_type = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{address}{type};
			my $address_bus  = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{address}{bus};
			my $driver_name  = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{driver}{name};
			my $device_bus   = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{device_bus};
			my $driver_type  = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{driver}{type};
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				's01:device_target' => $device_target,
				's02:alias'         => $alias, 
				's03:boot_order'    => $boot_order,
				's04:say_boot'      => $say_boot, 
				's05:type'          => $type, 
				's06:address_type'  => $address_type, 
				's07:address_bus'   => $address_bus, 
				's08:driver_name'   => $driver_name, 
				's09:device_bus'    => $device_bus, 
				's10:driver_type'   => $driver_type, 
			}});
			if ($device eq "disk")
			{
				my $address_domain   = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{address}{domain};
				my $address_slot     = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{address}{slot};
				my $address_function = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{address}{function};
				my $device_path      = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{path};
				my $driver_io        = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{driver}{io};
				my $driver_cache     = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{driver}{cache};
				my $on_lv            = $anvil->data->{server}{$short_host_name}{$server_name}{device}{$device_path}{on_lv};
				my $drbd_resource    = $anvil->data->{server}{$short_host_name}{$server_name}{device}{$device_path}{resource};
				my $drbd_volume      = $anvil->data->{lvm}{host_name}{$short_host_name}{lv_path}{$on_lv}{drbd}{volume};
				my $resource_size    = $anvil->data->{drbd}{host_name}{$short_host_name}{resource_name}{$drbd_resource}{volume}{$drbd_volume}{volume_size};
				my $lv_name          = $anvil->data->{lvm}{host_name}{$short_host_name}{lv_path}{$on_lv}{scan_lvm_lv_name};
				my $lv_size          = $anvil->data->{lvm}{host_name}{$short_host_name}{lv}{$lv_name}{scan_lvm_lv_size};
				my $metadata_size    = $lv_size - $resource_size;
				my $max_free_space   = get_max_free_space($anvil, $drbd_resource, $drbd_volume);
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					's01:address_domain'   => $address_domain,
					's02:address_slot'     => $address_slot, 
					's03:address_function' => $address_function, 
					's04:device_path'      => $device_path, 
					's05:driver_io'        => $driver_io, 
					's06:driver_cache'     => $driver_cache, 
					's07:on_lv'            => $on_lv, 
					's08:lv_name'          => $lv_name, 
					's09:drbd_resource'    => $drbd_resource, 
					's10:drbd_volume'      => $drbd_volume, 
					's11:resource_size'    => $anvil->Convert->bytes_to_human_readable({'bytes' => $resource_size})." (".$anvil->Convert->add_commas({number => $resource_size}).")", 
					's12:lv_size'          => $anvil->Convert->bytes_to_human_readable({'bytes' => $lv_size})."] (".$anvil->Convert->add_commas({number => $lv_size}).")", 
					's13:metadata_size'    => $anvil->Convert->bytes_to_human_readable({'bytes' => $metadata_size})."] (".$anvil->Convert->add_commas({number => $metadata_size}).")",
					's14:max_free_space'   => $max_free_space." (".$anvil->Convert->bytes_to_human_readable({'bytes' => $max_free_space}).")",
				}});
				
				print "- Target: [".$device_target."], boot: [".$say_boot."], Replication Volume: [".$drbd_resource."/".$drbd_volume."]\n";
				print " |- Resource / LV / Metadata sizes: [".$anvil->Convert->bytes_to_human_readable({'bytes' => $resource_size})." / ".$anvil->Convert->bytes_to_human_readable({'bytes' => $lv_size})." / ".$anvil->Convert->bytes_to_human_readable({'bytes' => $metadata_size})."], free space: [".$anvil->Convert->bytes_to_human_readable({'bytes' => $max_free_space})."]\n";
				#print " |- Resource / LV / Metadata sizes: [".$anvil->Convert->bytes_to_human_readable({'bytes' => $resource_size})." / ".$anvil->Convert->bytes_to_human_readable({'bytes' => $lv_size})." / ".$anvil->Convert->bytes_to_human_readable({'bytes' => $metadata_size})."], free space: [".$anvil->Convert->bytes_to_human_readable({'bytes' => $max_free_space})."], cache: [".$driver_cache."], IO Policy: [".$driver_io."]\n";
			}
			else
			{
				my $address_controller = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{address}{controller};
				my $address_unit       = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{address}{unit};
				my $address_target     = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{address}{target};
				my $device_path        = "<empty>";
				if (defined $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{path})
				{
					$device_path = $anvil->data->{server}{$short_host_name}{$server_name}{$from_source}{device}{$device}{target}{$device_target}{path};
				}
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					's1:address_controller' => $address_controller,
					's2:address_unit'       => $address_unit, 
					's3:address_target'     => $address_target, 
					's4:device_path'        => $device_path, 
				}});
				print "- Target: [".$device_target."], boot: [".$say_boot."], ISO: [".$device_path."]\n";
			}
		}
	}
	print "\n";
	
	print "Sub-Nodes:\n";
	show_volume($anvil, $drbd_resource, "node");
	
	my $dr_count = keys %{$anvil->data->{drbd_resource}{$drbd_resource}{host_type}{dr}{short_host_name}};
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { dr_count => $dr_count }});
	if ($dr_count)
	{
		print "DR Hosts:\n";
		show_volume($anvil, $drbd_resource, "dr");
	}
	
	return(0);
}

sub check_drbd_peer_access
{
	my ($anvil) = @_;
	
	my $all_online = 1;
	foreach my $this_host (sort {$a cmp $b} keys %{$anvil->data->{drbd}{drbd_node}})
	{
		my $host_uuid       = $anvil->Get->host_uuid_from_name({debug => 2, host_name => $this_host});
		my $short_host_name = $anvil->data->{hosts}{host_uuid}{$host_uuid}{short_host_name};
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			's1:this_host'       => $this_host, 
			's2:host_uuid'       => $host_uuid, 
			's3:short_host_name' => $short_host_name, 
		}});
		next if $host_uuid eq $anvil->Get->host_uuid;
		
		# This is used to store the IP we used to access the peer. If no access is available, this 
		# shows which hosts are not available.
		$anvil->data->{peer}{$short_host_name}{access_ip}      = "";
		$anvil->data->{peer}{$short_host_name}{access_network} = "";
		
		my $access  = 0;
		my $matches = $anvil->Network->find_access({
			debug  => 2,
			target => $this_host, 
		});
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { matches => $matches }});
		foreach my $preferred_network ("bcn", "mn", "ifn", "sn")
		{
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { preferred_network => $preferred_network }});
			foreach my $network_name (sort {$a cmp $b} keys %{$anvil->data->{network_access}})
			{
				next if $access;
				next if $network_name !~ /^$preferred_network/;
				my $target_ip   = $anvil->data->{network_access}{$network_name}{target_ip_address};
				my $test_access = $anvil->Remote->test_access({target => $target_ip});
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					's1:network_name' => $network_name, 
					's2:target_ip'    => $target_ip, 
					's3:test_access'  => $test_access, 
				}});
				
				if ($test_access)
				{
					# We're good.
					$access                                                 = 1;
					$anvil->data->{peer}{$short_host_name}{access}{ip}      = $target_ip;
					$anvil->data->{peer}{$short_host_name}{access}{network} = $network_name;
					$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
						's1:access'                                    => $access, 
						"s2:peer::${short_host_name}::access::ip"      => $anvil->data->{peer}{$short_host_name}{access}{ip}, 
						"s3:peer::${short_host_name}::access::network" => $anvil->data->{peer}{$short_host_name}{access}{network}, 
					}});
				}
			}
		}
		
		if (not $access)
		{
			$all_online = 0;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { all_online => $all_online }});
		}
	}
	
	return($all_online);
}

sub get_max_free_space
{
	my ($anvil, $drbd_resource, $drbd_volume) = @_;
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		's01:drbd_resource' => $drbd_resource,
		's02:drbd_volume'   => $drbd_volume,
	}});
	
	my $max_free_space = 0;
	foreach my $this_host (sort {$a cmp $b} keys %{$anvil->data->{drbd}{drbd_node}})
	{
		my $drbd_path        = $anvil->data->{drbd}{drbd_node}{$this_host}{config}{resource}{$drbd_resource}{volume}{$drbd_volume}{drbd_path};
		my $drbd_path_by_res = $anvil->data->{drbd}{drbd_node}{$this_host}{config}{resource}{$drbd_resource}{volume}{$drbd_volume}{drbd_path_by_res};
		my $backing_lv       = $anvil->data->{drbd}{drbd_node}{$this_host}{config}{resource}{$drbd_resource}{volume}{$drbd_volume}{backing_lv};
		my $lv_name          = $anvil->data->{lvm}{host_name}{$this_host}{lv_path}{$backing_lv}{scan_lvm_lv_name} ? $anvil->data->{lvm}{host_name}{$this_host}{lv_path}{$backing_lv}{scan_lvm_lv_name} : "";
		my $on_vg            = $anvil->data->{lvm}{host_name}{$this_host}{lv}{$lv_name}{scan_lvm_lv_on_vg}        ? $anvil->data->{lvm}{host_name}{$this_host}{lv}{$lv_name}{scan_lvm_lv_on_vg}        : "";
		my $vg_free_space    = $anvil->data->{lvm}{host_name}{$this_host}{vg}{$on_vg}{scan_lvm_vg_free}           ? $anvil->data->{lvm}{host_name}{$this_host}{vg}{$on_vg}{scan_lvm_vg_free}           : 0;
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			's01:this_host'        => $this_host,
			's02:drbd_path'        => $drbd_path, 
			's03:drbd_path_by_res' => $drbd_path_by_res, 
			's04:backing_lv'       => $backing_lv, 
			's05:on_vg'            => $on_vg, 
			's06:vg_free_space'    => $vg_free_space." (".$anvil->Convert->bytes_to_human_readable({'bytes' => $vg_free_space}).")",
		}});
		if ((not $max_free_space) or ($vg_free_space < $max_free_space))
		{
			$max_free_space = $vg_free_space;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				max_free_space => $max_free_space." (".$anvil->Convert->bytes_to_human_readable({'bytes' => $max_free_space}).")",
			}});
		}
	}
	
	return($max_free_space);
}

sub load_drbd_data
{
	my ($anvil, $drbd_resource) = @_;
	
	my $query = "
SELECT 
    a.host_uuid, 
    b.scan_drbd_resource_xml, 
    c.scan_drbd_volume_number, 
    c.scan_drbd_volume_device_path, 
    c.scan_drbd_volume_device_minor, 
    c.scan_drbd_volume_size 
FROM 
    hosts a, 
    scan_drbd_resources b, 
    scan_drbd_volumes c 
WHERE 
    a.host_uuid = b.scan_drbd_resource_host_uuid 
AND 
    b.scan_drbd_resource_uuid = c.scan_drbd_volume_scan_drbd_resource_uuid 
AND 
    b.scan_drbd_resource_name = ".$anvil->Database->quote($drbd_resource)."
;";
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { query => $query }});
	
	my $results = $anvil->Database->query({query => $query, source => $THIS_FILE, line => __LINE__});
	my $count   = @{$results};
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		results => $results, 
		count   => $count, 
	}});
	foreach my $row (@{$results})
	{
		my $host_uuid               = $row->[0];
		my $short_host_name         = $anvil->data->{hosts}{host_uuid}{$host_uuid}{short_host_name};
		my $host_type               = $anvil->data->{hosts}{host_uuid}{$host_uuid}{host_type};
		my $scan_drbd_volume_number = $row->[2];
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			's1:host_uuid'               => $host_uuid, 
			's2:host_type'               => $host_type, 
			's3:short_host_name'         => $short_host_name, 
			's4:scan_drbd_volume_number' => $scan_drbd_volume_number, 
		}});
		
		$anvil->data->{drbd_resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$scan_drbd_volume_number}{device_path}  = $row->[3];
		$anvil->data->{drbd_resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$scan_drbd_volume_number}{device_minor} = $row->[4];
		$anvil->data->{drbd_resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$scan_drbd_volume_number}{volume_size}  = $row->[5];
		$anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}{$short_host_name}{host_uuid}          = $host_uuid;
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			"s1:drbd_resource::${drbd_resource}::host_uuid::${host_uuid}::volume_number::${scan_drbd_volume_number}::device_path"  => $anvil->data->{drbd_resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$scan_drbd_volume_number}{device_path}, 
			"s2:drbd_resource::${drbd_resource}::host_uuid::${host_uuid}::volume_number::${scan_drbd_volume_number}::device_minor" => $anvil->data->{drbd_resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$scan_drbd_volume_number}{device_minor}, 
			"s3:drbd_resource::${drbd_resource}::host_uuid::${host_uuid}::volume_number::${scan_drbd_volume_number}::volume_size"  => $anvil->data->{drbd_resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$scan_drbd_volume_number}{volume_size}, 
			"s4:drbd_resource::${drbd_resource}::host_type::${host_type}::short_host_name::${short_host_name}::host_uuid"          => $anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}{$short_host_name}{host_uuid}, 
		}});
		
		if (not exists $anvil->data->{drbd_resource}{$drbd_resource}{xml})
		{
			$anvil->data->{drbd_resource}{$drbd_resource}{xml} = $row->[1];
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				"drbd_resource::${drbd_resource}::xml" => $anvil->data->{drbd_resource}{$drbd_resource}{xml}, 
			}});
			$anvil->DRBD->parse_resource({
				debug => 2, 
				xml   => $anvil->data->{drbd_resource}{$drbd_resource}{xml}, 
			});
		}
	}
	
	return(0);
}

sub show_volume
{
	my ($anvil, $drbd_resource, $host_type) = @_;
	
	my $anvil_uuid = defined $anvil->data->{switches}{anvil_uuid} ? $anvil->data->{switches}{anvil_uuid} : $anvil->Cluster->get_anvil_uuid();
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { anvil_uuid => $anvil_uuid }});
	foreach my $short_host_name (sort {$a cmp $b} keys %{$anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}})
	{
		my $host_uuid = $anvil->data->{drbd_resource}{$drbd_resource}{host_type}{$host_type}{short_host_name}{$short_host_name}{host_uuid};
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			's1:short_host_name' => $short_host_name,
			's2:host_uuid'       => $host_uuid, 
		}});
		print " |- Name: [".$short_host_name."], UUID: [".$host_uuid."]\n";
		foreach my $volume_number (sort {$a cmp $b} keys %{$anvil->data->{drbd_resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}})
		{
			my $device_path        = $anvil->data->{drbd_resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$volume_number}{device_path};
			my $device_minor       = $anvil->data->{drbd_resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$volume_number}{device_minor};
			my $volume_size        = $anvil->data->{drbd_resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$volume_number}{volume_size};
			my $backing_disk       = $anvil->data->{new}{resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$volume_number}{backing_disk};
			my $meta_disk          = $anvil->data->{new}{resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$volume_number}{meta_disk};
			my $storage_group_uuid = $anvil->data->{new}{resource}{$drbd_resource}{host_uuid}{$host_uuid}{volume_number}{$volume_number}{storage_group_uuid};
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				's1:volume_number'      => $volume_number,
				's2:device_path'        => $device_path, 
				's3:device_minor'       => $device_minor, 
				's4:volume_size'        => $volume_size, 
				's5:backing_disk'       => $backing_disk, 
				's6:meta_disk'          => $meta_disk, 
				's7:storage_group_uuid' => $storage_group_uuid, 
			}});
			my $storage_group_name       = "<unknown>";
			my $storage_group_size       = 0;
			my $storage_group_free_space = 0;
			if (($storage_group_uuid) && ($anvil_uuid) && (exists $anvil->data->{anvil_resources}{$anvil_uuid}{storage_group}{$storage_group_uuid}))
			{
				$storage_group_name       = $anvil->data->{storage_groups}{storage_group_uuid}{$storage_group_uuid}{storage_group_name};
				$storage_group_size       = $anvil->data->{anvil_resources}{$anvil_uuid}{storage_group}{$storage_group_uuid}{vg_size};
				$storage_group_free_space = $anvil->data->{anvil_resources}{$anvil_uuid}{storage_group}{$storage_group_uuid}{free_size};
			}
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				's1:storage_group_size'       => $storage_group_size,
				's2:storage_group_free_space' => $storage_group_free_space, 
			}});
			print "   |- Volume: [".$volume_number."], backing device: [".$backing_disk."], DRBD minor: [".$device_minor."], size: [".$anvil->Convert->bytes_to_human_readable({'bytes' => $volume_size})."]\n";
			print "   ^- In storage group: [".$storage_group_name."], size: [".$anvil->Convert->bytes_to_human_readable({'bytes' => $storage_group_size})."], free: [".$anvil->Convert->bytes_to_human_readable({'bytes' => $storage_group_free_space})."]\n";
			
			# How much space is available in the storage group this volume is in?
			foreach my $this_scan_lvm_lv_name (sort {$a cmp $b} keys %{$anvil->data->{lvm}{host_name}{$short_host_name}{lv}})
			{
				my $this_scan_lvm_lv_path  = $anvil->data->{lvm}{host_name}{$short_host_name}{lv}{$this_scan_lvm_lv_name}{scan_lvm_lv_path}; 
				my $this_scan_lvm_lv_on_vg = $anvil->data->{lvm}{host_name}{$short_host_name}{lv}{$this_scan_lvm_lv_name}{scan_lvm_lv_on_vg}; 
				my $this_scan_lvm_lv_uuid  = $anvil->data->{lvm}{host_name}{$short_host_name}{lv}{$this_scan_lvm_lv_name}{scan_lvm_lv_uuid};
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					's1:this_scan_lvm_lv_name'  => $this_scan_lvm_lv_name, 
					's2:this_scan_lvm_lv_path'  => $this_scan_lvm_lv_path,
					's3:this_scan_lvm_lv_on_vg' => $this_scan_lvm_lv_on_vg, 
					's4:this_scan_lvm_lv_uuid'  => $this_scan_lvm_lv_uuid, 
				}});
				if ($backing_disk eq $this_scan_lvm_lv_path)
				{
					# What's the VG's UUID? 
					$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
						's1:short_host_name'        => $short_host_name, 
						's2:this_scan_lvm_lv_on_vg' => $this_scan_lvm_lv_on_vg, 
					}});
					if (exists $anvil->data->{lvm}{host_name}{$short_host_name}{vg}{$this_scan_lvm_lv_on_vg})
					{
						my $scan_lvm_vg_internal_uuid = $anvil->data->{lvm}{host_name}{$short_host_name}{vg}{$this_scan_lvm_lv_on_vg}{scan_lvm_vg_internal_uuid};
						my $storage_group_uuid        = $anvil->data->{lvm}{host_name}{$short_host_name}{vg}{$this_scan_lvm_lv_on_vg}{storage_group_uuid};
						$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
							's1:scan_lvm_vg_internal_uuid' => $scan_lvm_vg_internal_uuid, 
							's2:storage_group_uuid'        => $storage_group_uuid, 
						}});
						
						if ($storage_group_uuid)
						{
							my $vg_size   = $anvil->data->{anvil_resources}{$anvil_uuid}{storage_group}{$storage_group_uuid}{vg_size};
							my $free_size = $anvil->data->{anvil_resources}{$anvil_uuid}{storage_group}{$storage_group_uuid}{free_size};
						}
					}
				}
			}
		}
	}
	
	return(0);
}

sub validate_server
{
	my ($anvil) = @_;
	
	$anvil->Get->server_from_switch({
		debug      => 2, 
		string     => $anvil->data->{switches}{server},
		anvil_uuid => $anvil->data->{switches}{anvil_uuid},
	});
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		"switches::server_name" => $anvil->data->{switches}{server_name},
		"switches::server_uuid" => $anvil->data->{switches}{server_uuid},
	}});
	
	if (not $anvil->data->{switches}{server_uuid})
	{
		show_server_list($anvil);
		if ($anvil->data->{switches}{anvil_uuid})
		{
			# Not found on the requested Anvil! node.
			print "\nThe server: [".$anvil->data->{switches}{server}."] was not found on the Anvil! node: [".$anvil->data->{switches}{anvil_name}."]. Valid servers are above.\n\n";
		}
		else
		{
			# Not found at all.
			print "\nThe server: [".$anvil->data->{switches}{server}."] was not found. Valid servers are above.\n\n";
		}
		$anvil->nice_exit({exit_code => 1});
	}
	
	print "Working with the server: [".$anvil->data->{switches}{server_name}."], UUID: [".$anvil->data->{switches}{server_uuid}."]\n";
	my $short_host_name   = $anvil->Get->short_host_name;
	my $server_name       = $anvil->data->{switches}{server_name};
	my $server_uuid       = $anvil->data->{switches}{server_uuid};
	my $server_definition = $anvil->data->{servers}{server_uuid}{$server_uuid}{server_definition_xml};
	my $server_host_uuid  = $anvil->data->{servers}{server_uuid}{$server_uuid}{server_host_uuid};
	my $server_state      = $anvil->data->{servers}{server_uuid}{$server_uuid}{server_state};
	my $anvil_uuid        = $anvil->data->{servers}{server_uuid}{$server_uuid}{server_anvil_uuid};
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		's1:short_host_name'   => $short_host_name, 
		's2:server_name'       => $server_name, 
		's3:server_uuid'       => $server_uuid, 
		's4:server_definition' => $server_definition,
		's5:server_host_uuid'  => $server_host_uuid, 
		's6:server_state'      => $server_state, 
		's7:anvil_uuid'        => $anvil_uuid, 
	}});
	if (not $anvil->data->{switches}{anvil_uuid})
	{
		$anvil->data->{switches}{anvil_uuid} = $anvil_uuid;
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			's1:switches::anvil_uuid' => $anvil->data->{switches}{anvil_uuid}, 
		}});
	}
	
	if ($server_state eq "DELETED")
	{
		print "The server: [".$server_name."] has been deleted.\n";
		$anvil->nice_exit({exit_code => 1});
	}
	
	# Parse the definition.
	$anvil->Server->parse_definition({
		debug      => 3,
		host       => $short_host_name,
		server     => $server_name, 
		source     => "from_db",
		definition => $server_definition, 
	});
	
	# Can we read the XML definition?
	$anvil->Server->get_status({
		debug  => 2,
		server => $server_name,
		host   => $short_host_name,
	});
	
	if (not $anvil->data->{server}{$short_host_name}{$server_name}{from_virsh}{xml})
	{
		# The server isn't actually running... Not here anyway.
		if ($server_state eq "running")
		{
			my $server_host_name = $anvil->Database->get_host_from_uuid({
				short     => 1,
				host_uuid => $server_host_uuid,
			});
			
			print "The server: [".$server_name."] appears to be running on: [".$server_host_name."], please run this on that host.\n";
			$anvil->nice_exit({exit_code => 1});
		}
	}
	
	return(0);
}

# Update the definition on disk and in the DB, and define or undefine if requested.
sub update_definition
{
	my ($anvil, $task) = @_;
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { task => $task }});
	
	my $short_host_name     = $anvil->Get->short_host_name;
	my $server_name         = $anvil->data->{switches}{server_name};
	my $server_uuid         = $anvil->data->{switches}{server_uuid};
	my $server_definition   = $anvil->data->{servers}{server_uuid}{$server_uuid}{server_definition_xml};
	my $server_host_uuid    = $anvil->data->{servers}{server_uuid}{$server_uuid}{server_host_uuid};
	my $server_state        = $anvil->data->{servers}{server_uuid}{$server_uuid}{server_state};
	my $definition_file     = $anvil->data->{path}{directories}{shared}{definitions}."/".$server_name.".xml";
	my $server_running_here = 0;
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		's1:short_host_name'   => $short_host_name, 
		's2:server_name'       => $server_name, 
		's3:server_uuid'       => $server_uuid, 
		's4:server_definition' => $server_definition,
		's5:server_host_uuid'  => $server_host_uuid, 
		's6:server_state'      => $server_state, 
		's7:definition_file'   => $definition_file, 
	}});
	
	# See if the server is running locally
	my $shell_call = $anvil->data->{path}{exe}{setsid}." --wait ".$anvil->data->{path}{exe}{virsh}." list --name";
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { shell_call => $shell_call }});
	
	my ($output, $return_code) = $anvil->System->call({debug => 2, shell_call => $shell_call});
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		's1:output'      => $output,
		's2:return_code' => $return_code, 
	}});
	foreach my $this_server (split/\n/, $output)
	{
		$this_server = $anvil->Words->clean_spaces({string => $this_server});
		next if not $this_server;
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { this_server => $this_server }});
		
		if ($this_server eq $server_name)
		{
			$server_running_here = 1;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { server_running_here => $server_running_here }});
			last;
		}
	}
	
	my $disk_definition  = $anvil->data->{server}{$short_host_name}{$server_name}{from_disk}{xml}  ? $anvil->data->{server}{$short_host_name}{$server_name}{from_disk}{xml}  : "";
	my $virsh_definition = $anvil->data->{server}{$short_host_name}{$server_name}{from_virsh}{xml} ? $anvil->data->{server}{$short_host_name}{$server_name}{from_virsh}{xml} : "";
	my $use_definition   = "";
	if (($server_running_here) or (($server_state eq "running") && ($virsh_definition)))
	{
		# Get the live definition
		if ($server_running_here)
		{
			my $shell_call = $anvil->data->{path}{exe}{setsid}." --wait ".$anvil->data->{path}{exe}{virsh}." dumpxml --inactive ".$server_name;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { shell_call => $shell_call }});
			
			my ($live_virsh_definition, $return_code) = $anvil->System->call({shell_call => $shell_call, source => $THIS_FILE, line => __LINE__});
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
				live_virsh_definition => $live_virsh_definition, 
				return_code           => $return_code,
			}});
			
			my ($problem) = $anvil->Server->parse_definition({
				server     => $server_name,
				source     => "from_virsh", 
				definition => $live_virsh_definition, 
			});
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { problem => $problem }});
			if (not $problem)
			{
				$use_definition = $live_virsh_definition;
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { use_definition => $use_definition }});
				
				$anvil->Server->parse_definition({
					debug      => 3,
					host       => $short_host_name,
					server     => $server_name, 
					source     => "from_virsh",
					definition => $live_virsh_definition, 
				});
			}
			else
			{
				$use_definition = $virsh_definition;
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { use_definition => $use_definition }});
				
				$anvil->Server->parse_definition({
					debug      => 3,
					host       => $short_host_name,
					server     => $server_name, 
					source     => "from_virsh",
					definition => $virsh_definition, 
				});
			}
		}
		else
		{
			$use_definition = $virsh_definition;
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { use_definition => $use_definition }});
			
			$anvil->Server->parse_definition({
				debug      => 3,
				host       => $short_host_name,
				server     => $server_name, 
				source     => "from_virsh",
				definition => $virsh_definition, 
			});
		}
	}
	else
	{
		$use_definition = $disk_definition;
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { use_definition => $use_definition }});
		
		$anvil->Server->parse_definition({
			debug      => 3,
			host       => $short_host_name,
			server     => $server_name, 
			source     => "from_disk",
			definition => $virsh_definition, 
		});
	}
	
	if (not $use_definition)
	{
		# What?!
		print "[ Error ] - Failed to find an on disk or from virsh definition for the server: [".$server_name."]. Unable to proceed.\n";
		$anvil->nice_exit({exit_code => 1});
	}
	
	# Update the stored definition
	$anvil->data->{servers}{server_uuid}{$server_uuid}{server_definition_xml} = $use_definition;
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
		"servers::server_uuid::${server_uuid}::server_definition_xml" => $anvil->data->{servers}{server_uuid}{$server_uuid}{server_definition_xml},
	}});
	
	# Update the on-disk definition
	my ($failed) = $anvil->Storage->write_file({
		secure    => 1, 
		file      => $definition_file, 
		body      => $use_definition, 
		overwrite => 1,
	});
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { failed => $failed }});
	my $server_definition_uuid = $anvil->Database->insert_or_update_server_definitions({
		debug                         => 2,
		server_definition_xml         => $use_definition,  
		server_definition_server_uuid => $server_uuid, 
	});
	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 3, list => { server_definition_uuid => $server_definition_uuid }});
	
	if ($task eq "define")
	{
		# Define the server.
		my $shell_call = $anvil->data->{path}{exe}{setsid}." --wait ".$anvil->data->{path}{exe}{virsh}." define ".$definition_file,
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { shell_call => $shell_call }});
		
		my ($output, $return_code) = $anvil->System->call({shell_call => $shell_call, source => $THIS_FILE, line => __LINE__});
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			output      => $output, 
			return_code => $return_code,
		}});
	}
	elsif ($task eq "undefine")
	{
		# Undefine the server.
		my $shell_call = $anvil->data->{path}{exe}{setsid}." --wait ".$anvil->data->{path}{exe}{virsh}." undefine ".$server_name,
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { shell_call => $shell_call }});
		
		my ($output, $return_code) = $anvil->System->call({
			debug      => 2,
			shell_call => $shell_call, 
			source     => $THIS_FILE, 
			line       => __LINE__,
		});
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			output      => $output, 
			return_code => $return_code,
		}});
	}
	
	return(0);
}

sub show_server_list
{
	my ($anvil) = @_;
	
	# Loop through all Anvil! nodes, then all server in that Anvil!
	foreach my $anvil_name (sort {$a cmp $b} keys %{$anvil->data->{anvils}{anvil_name}})
	{
		my $anvil_uuid        = $anvil->data->{anvils}{anvil_name}{$anvil_name}{anvil_uuid};
		my $anvil_description = $anvil->data->{anvils}{anvil_name}{$anvil_name}{anvil_description};
		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
			anvil_name        => $anvil_name, 
			anvil_uuid        => $anvil_uuid,
			anvil_description => $anvil_description,
		}});
		if (($anvil->data->{switches}{anvil_uuid}) && ($anvil->data->{switches}{anvil_uuid} ne $anvil_uuid))
		{
			next;
		}
		print "\nAnvil! Node: [".$anvil_name."], UUID: [".$anvil_uuid."] - Description: [".$anvil_description."]\n";
		
		my $server_count = 0;
		if (exists $anvil->data->{servers}{anvil_uuid}{$anvil_uuid}{server_name})
		{
			$server_count = keys %{$anvil->data->{servers}{anvil_uuid}{$anvil_uuid}{server_name}};
			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { server_count => $server_count }});
		}
		if (not $server_count)
		{
			print "- No servers on this node yet\n";
		}
		else
		{
			foreach my $server_name (sort {$a cmp $b} keys %{$anvil->data->{servers}{anvil_uuid}{$anvil_uuid}{server_name}})
			{
				my $server_uuid  = $anvil->data->{servers}{anvil_uuid}{$anvil_uuid}{server_name}{$server_name}{server_uuid};
				my $server_state = $anvil->data->{servers}{server_uuid}{$server_uuid}{server_state};
				$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
					server_name  => $server_name, 
					server_uuid  => $server_uuid, 
					server_state => $server_state,
				}});
				next if $server_state eq "DELETED";
				print "^- Server: [".$server_name."], UUID: [".$server_uuid."]\n";
			}
		}
	}
	
	return(0);
}