Backup communication system for PowerHA SystemMirror GUI

Use this information to know how the PowerHA SystemMirror GUI deploys a backup communication system.

The PowerHA SystemMirror GUI creates a backup communication method for the PowerHA SystemMirror GUI server by configuring the Secure Shell (SSH) key. If the communication between the PowerHA SystemMirror GUI server and PowerHA SystemMirror GUI agent is lost, the backup communication method can be used to restore communication. During the cluster creation or cluster addition process, you have to confirm if you want to enable the SSH backup communication. After you enable the SSH backup communication, it remains enabled for each new cluster that you add or create.

PowerHA SystemMirror performs the following steps on each node in the cluster:
  1. Creates a user and group called smui. The smui user will have limited access to some of the PowerHA SystemMirror files.
  2. Installs the public key of the PowerHA SystemMirror GUI server on each node in the cluster for the smui user.
The private key is created and stored on the PowerHA SystemMirror GUI server in a secured folder with root-only access.
Note: The PowerHA SystemMirror GUI uses the backup communication system only for communication problems. It is not used during normal operations.