* A resource agent receives all configuration information about the resource it manages via environment variables. The names of these environment variables are always the name of the resource parameter, prefixed with OCF_RESKEY_. For example, if the resource has an ip parameter set to 192.168.1.1, then the resource agent will have access to an environment variable OCF_RESKEY_ip holding that value.
# monitor -(status aliases here) Queries the resource for its state.
# meta-data -Dumps the resource agent metadata.
# promote -Turns a resource into the Master role (Master/Slave resources only).
# demote -Turns a resource into the Slave role (Master/Slave resources only).
# migrate_to - migration target
# migrate_from-Implement live migration of resources.
# validate-all-Validates a resource’s configuration.
# help -(usage maps here) Displays a usage message when the resource agent is invoked from the command line, rather than by the cluster manager.
# notify -Inform resource about changes in state of other clones.
if ($conf->{switches}{start})
{
# Start the server
start_server($conf);
}
elsif ($conf->{switches}{stop})
{
# Stop the server
stop_server($conf);
}
elsif (($conf->{switches}{monitor}) or ($conf->{switches}{status}))
{
# Report the status of the server.
server_status($conf);
}
elsif (($conf->{switches}{metadaata}) or ($conf->{switches}{'meta-data'}))
{
show_metadata($conf);
}
elsif ($conf->{switches}{promote})
{
# We don't support this, so we return OCF_ERR_UNIMPLEMENTED (3)
to_log($conf, {message => "We were asked to promote: [".$conf->{environment}{OCF_RESKEY_name}."], which makes no sense and is not supported. Ignoreing.", 'line' => __LINE__, level => 0, priority => "err"});
exit(3);
}
elsif ($conf->{switches}{demote})
{
# We don't support this, so we return OCF_ERR_UNIMPLEMENTED (3)
to_log($conf, {message => "We were asked to demote: [".$conf->{environment}{OCF_RESKEY_name}."], which makes no sense and is not supported. Ignoreing.", 'line' => __LINE__, level => 0, priority => "err"});
to_log($conf, {message => "We were asked to notify, but this is not a promotable (we're stateless) agent. Ignoring.", 'line' => __LINE__, level => 0, priority => "warn"});
exit(3);
}
else
{
# We were called in some unexpected way. Log an error, show usage and exit.
to_log($conf, {message => "We were invoked with an unexpected (or no) command. Environment variables and arguments below.", 'line' => __LINE__, level => 0, priority => "warn"});
to_log($conf, {message => "The environment variable 'OCF_RESKEY_CRM_meta_timeout' was not set, so setting it to: [".$conf->{environment}{OCF_RESKEY_CRM_meta_timeout}."].", 'line' => __LINE__, level => 1, priority => "warn"});
}
my $return_code = undef;
my $output = [];
my $current_time = time;
my $timeout = $current_time + int(($conf->{environment}{OCF_RESKEY_CRM_meta_timeout} /= 1000) / 2);
to_log($conf, {message => "The 'virsh' call exited with the return code: [$return_code]. The 'libvirtd' may have failed to start. We won't wait any longer.", 'line' => __LINE__, level => 1, priority => "warn"});
}
else
{
to_log($conf, {message => "The 'virsh' call exited with the return code: [$return_code]. The 'libvirtd' service might be starting, so we will check again shortly.", 'line' => __LINE__, level => 2});
sleep 2;
}
}
# If I got a non-zero return code, something went wrong with the virsh call.
if ($return_code)
{
to_log($conf, {message => "It would appear that libvirtd is not operating (or not operating correctly). Expected the return code '0' but got: [$return_code].", 'line' => __LINE__, level => 0, priority => "err"});
# running - The domain is currently running on a CPU
# paused - The domain has been paused, usually occurring through the administrator
# running virsh suspend. When in a paused state the domain will still consume
# allocated resources like memory, but will not be eligible for scheduling by
# the hypervisor.
# pmsuspended - The domain has been suspended by guest power management, e.g. entered into s3
# state.
# in shutdown - The domain is in the process of shutting down, i.e. the guest operating
# system has been notified and should be in the process of stopping its
# operations gracefully.
## States we'll return OCF_NOT_RUNNING (7).
# shut off - The domain is not running. Usually this indicates the domain has been shut
# down completely, or has not been started.
## States we'll return OCF_ERR_GENERIC (1).
# idle - The domain is idle, and not running or runnable. This can be caused because
# the domain is waiting on IO (a traditional wait state) or has gone to sleep
# because there was nothing else for it to do.
# crashed - The domain has crashed, which is always a violent ending. Usually this state
# can only occur if the domain has been configured not to restart on crash.
if (($state eq "running") or ($state eq "paused") or ($state eq "pmsuspended") or ($state eq "in shutdown"))
{
to_log($conf, {message => "The server: [$server] is: [$state], which is OK.", 'line' => __LINE__, level => 1});
exit(0);
}
elsif ($state eq "shut off")
{
to_log($conf, {message => "The server: [$server] is: [$state].", 'line' => __LINE__, level => 1});
exit(7);
}
elsif (($state eq "idle") or ($state eq "crashed"))
{
to_log($conf, {message => "The server: [$server] is in a bad state: [$state]!", 'line' => __LINE__, level => 0}, priority => "err");
exit(1);
}
else
{
# WTF?
to_log($conf, {message => "The server: [$server] is in an unexpected state: [$state]!", 'line' => __LINE__, level => 0}, priority => "err");
exit(1);
}
}
else
{
# Not running. Exit with OCF_NOT_RUNNING
to_log($conf, {message => "The server: [$server] is not running on this node.", 'line' => __LINE__, level => 1});
exit(7);
}
exit(0);
}
# Migrate the server
sub migrate_server
{
my ($conf) = @_;
# If we were given 'migrate_to', then just verify that the node name makes sense. If we were given
# 'migrate_from', we need to find the peer.
# Return failed until this is actually implemented.
exit(1);
}
# Validation checks that we have the definition XML, resource config and that needed apps are installed.
sub validate
{
my ($conf) = @_;
### Exit options;
# OCF_SUCCESS (0)-all is well.
# OCF_ERR_CONFIGURED (6)-the user has misconfigured the resource (the server name doesn't exist).
# OCF_ERR_INSTALLED (5) -The resource has possibly been configured correctly, but a vital component is missing on the node where validate-all is being executed.
# OCF_ERR_PERM (4) -the resource is configured correctly and is not missing any required components, but is suffering from a permission issue (such as not being able to create a necessary file).
exit(0);
}
# This makes a system call and returns the return code and the output as an array reference of lines.
Digimer
7 years ago