fix(cgi-bin): don't insert when using existing pipe

cgi-bin/manage_vnc_pipes

@@ -247,6 +247,7 @@ sub start_websockify
 		$ws_info                = {};
 		$ws_info->{pid}         = $existing_websockify->{ws_pid};
 		$ws_info->{source_port} = $existing_websockify->{ssh_tunnel_forward_port};
+		$ws_info->{is_existing} = 1;
 	}
 	else
 	{
@@ -329,6 +330,7 @@ sub start_ssh_tunnel
 	{
 		$ssh_tunnel_info                = {};
 		$ssh_tunnel_info->{pid}         = $existing_ssh_tunnel->{ssh_tunnel_pid};
+		$ssh_tunnel_info->{is_existing} = 1;
 	}
 	else
 	{
@@ -636,6 +638,8 @@ sub open_vnc_pipe
 		return;
 	}
 
+	if (not $ws_info->{is_existing} or not $ssh_tunnel_info->{is_existing})
+	{
 		insert_vnc_pipe({
 			server_uuid             => $server_uuid,
 			server_vnc_port         => $vnc_info->{port},
@@ -646,6 +650,7 @@ sub open_vnc_pipe
 			ssh_tunnel_forward_port => $ws_info->{source_port}
 		});
 	}
+}
 
 sub close_vnc_pipe
 {