The first step to configuring fence devices is to check and turn on the STONITH cluster feature. You can see the status of the STONITH feature by running the pcs property list command. In the following screenshot, you can see the output of this command:
You can see in the stonith-enabled line that the STONITH feature is currently disabled.
You can enable the STONITH feature by running the pcs property set stonith-enabled=true command. In the following screenshot, you can see the command used to enable STONITH and the output afterwards:
You can see in the stonith-enabled line that the STONITH feature is now enabled.
To continue configuring the fence devices, you must install the fence agents on all of your cluster nodes. You can install all the fencing agents available in CentOS 7 with one command. In the following screenshot, you can see the command used to install all available fencing agents:
Note that you must repeat this process on all cluster nodes.