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2.5. Testing the Resource Configuration

In the cluster status display shown in Section 2.4, “Creating the Resources and Resource Groups with the pcs Command”, all of the resources are running on node z1.example.com. You can test whether the resource group fails over to node z2.example.com by using the following procedure to put the first node in standby mode, after which the node will no longer be able to host resources.
  1. The following command puts node z1.example.com in standby mode.
    root@z1 ~]# pcs cluster standby z1.example.com
  2. After putting node z1 in standby mode, check the cluster status. Note that the resources should now all be running on z2.
    [root@z1 ~]# pcs status
    Cluster name: my_cluster
    Last updated: Wed Jul 31 17:16:17 2013
    Last change: Wed Jul 31 17:18:34 2013 via crm_attribute on z1.example.com
    Stack: corosync
    Current DC: z2.example.com (2) - partition with quorum
    Version: 1.1.10-5.el7-9abe687
    2 Nodes configured
    6 Resources configured
    
    
    Node z1.example.com (1): standby
    Online: [ z2.example.com ]
    
    Full list of resources:
    
     myapc	(stonith:fence_apc_snmp):	Started z1.example.com 
     Resource Group: apachegroup
         my_lvm	(ocf::heartbeat:LVM):	Started z2.example.com 
         my_fs	(ocf::heartbeat:Filesystem):	Started z2.example.com 
         VirtualIP	(ocf::heartbeat:IPaddr2):	Started z2.example.com 
         Website	(ocf::heartbeat:apache):	Started z2.example.com
    
    The web site at the defined IP address should still display, without interruption.
  3. To remove z1 from standby mode, enter the following command.
    root@z1 ~]# pcs cluster unstandby z1.example.com

    Note

    Removing a node from standby mode does not in itself cause the resources to fail back over to that node. For information on controlling which node resources can run on, see the chapter on configuring cluster resources in the Red Hat High Availability Add-On Reference.