4.3. Creating a high availability cluster

Procedure

1. Authenticate the pcs user hacluster for each node in the cluster on the node from which you will be running pcs.

   The following command authenticates user hacluster on z1.example.com for both of the nodes in a two-node cluster that will consist of z1.example.com and z2.example.com.

   [root@z1 ~]# pcs host auth z1.example.com z2.example.com

   Username: *hacluster*
   Password:
   z1.example.com: Authorized
   z2.example.com: Authorized

2. Run the following command from z1.example.com to create the two-node cluster my_cluster that consists of nodes z1.example.com and z2.example.com. This will propagate the cluster configuration files to both nodes in the cluster. This command includes the --start option, which will start the cluster services on both nodes in the cluster.

   [root@z1 ~]# pcs cluster setup my_cluster --start z1.example.com z2.example.com

3. Enable the cluster services to run on each node in the cluster when the node is booted.

   참고

   For your particular environment, you can skip this step by keeping the cluster services disabled. If enabled and a node goes down, any issues with your cluster or your resources are resolved before the node rejoins the cluster. If you keep the cluster services disabled, you need to manually start the services when you reboot a node by executing the pcs cluster start command on that node.

   [root@z1 ~]# pcs cluster enable --all

4. Display the status of the cluster you created with the pcs cluster status command. Because there could be a slight delay before the cluster is up and running when you start the cluster services with the --start option of the pcs cluster setup command, you should ensure that the cluster is up and running before performing any subsequent actions on the cluster and its configuration.

   [root@z1 ~]# pcs cluster status

   Cluster Status:
    Stack: corosync
    Current DC: z2.example.com (version 2.0.0-10.el8-b67d8d0de9) - partition with quorum
    Last updated: Thu Oct 11 16:11:18 2018
    Last change: Thu Oct 11 16:11:00 2018 by hacluster via crmd on z2.example.com
    2 Nodes configured
    0 Resources configured
   
   ...