Creating Resources

You can create a resource by using the pcs resource create command as shown in the following example that creates a resource for a virtual IP address: 

sudo pcs resource create MyVirtualIP ocf:heartbeat:IPaddr2 ip=192.0.2.3 \
cidr_netmask=24 nic=eth1 \
op monitor interval=1s group myapachegroup --future

In the preceding example:

  • MyVirtualIP is the id, or name of the resource.

  • ocf is the class, or the standard, the resource agent conforms to.

  • heartbeat is the provider of the resource.

  • IPaddr2 is the type of resource that is to be created.

    The following options are specified for the IPaddr2 resource:

    • ip=192.0.2.3 specifies IP address to use for the Virtual IP Address.

    • cidr_netmask=24 specifies the netmask for the interface in CIDR format.

    • nic=eth1 The base network interface on which the IP address will be brought online.

    The following operation is specified for the IPaddr2 resource:

    • op monitor interval=1s specifies that the system checks every second whether the resource is running.

  • group myapachegroup specifies the resource group to which the resource is to be added. If the group does not exist, it is created.

  • --future is specified to use the command's latest syntax and options.

Note:

The preceding example includes the --future flag in its parameter list and therefore uses the newer group option (in place of the deprecated --group). See Oracle Linux 10: Release Notes for Oracle Linux 10 and the pcs(8) manual page for more information.

Following on from the preceding example, you can create and add a second resource, this time of type apache, as shown in the following example: 

sudo pcs resource create MyApacheWebsite ocf:heartbeat:apache \
configfile="/etc/httpd/conf/httpd.conf" \
statusurl="http://192.0.2.3/server-status" group myapachegroup --future

You can confirm the status of your resources by running the pcs status command. Depending upon your configuration, your command output will be similar to the following sample code block: 

sudo pcs status
Cluster name: my_cluster
Cluster Summary:
* Stack: corosync (Pacemaker is running)
* Current DC: node1 (version 2.1.6-9.1.0.1.el8_9-
6fdc9deea29) - partition with quorum
* Last updated: Sat Feb 3 22:35:58 2024 on node1
* Last change: Sat Feb 3 22:33:37 2024 by root via
cibadmin on node1
* 2 nodes configured
* 4 resource instances configured
Node List:
* Online: [ node1 ]
* OFFLINE: [ node2 ]
Full List of Resources:
* Resource Group: myapachegroup:
 * MyVirtualIP (ocf::heartbeat:IPaddr2): Started node1
 * MyApacheWebsite (ocf::heartbeat:apache): Started node1
...
...
Daemon Status:
corosync: active/disabled
pacemaker: active/enabled
pcsd: active/enabled