The mmexpelnode command

The mmexpelnode command instructs the cluster manager to expel the target nodes and to run the normal recovery protocol.

The cluster manager keeps a list of the expelled nodes. Expelled nodes will not be allowed to rejoin the cluster until they are removed from the list using the -r or --reset option on the mmexpelnode command. The expelled nodes information will also be reset if the cluster manager node goes down or is changed with mmchmgr -c.

The syntax of the mmexpelnode command is:

mmexpelnode [-o | --once] [-f | --is-fenced] [-w | --wait] -N Node[,Node...]

Or,

mmexpelnode {-l | --list}

Or,

mmexpelnode {-r | --reset} -N {all | Node[,Node...]}

The flags used by this command are:

-o | --once: Specifies that the nodes should not be prevented from rejoining. After the recovery protocol completes, expelled nodes will be allowed to rejoin the cluster immediately, without the need to first invoke mmexpelnode --reset.
-f | --is-fenced: Specifies that the nodes are fenced out and precluded from accessing any GPFS™ disks without first rejoining the cluster (for example, the nodes were forced to reboot by turning off power). Using this flag allows GPFS to start log recovery immediately, skipping the normal 35-second wait.
-w | --wait: Instructs the mmexpelnode command to wait until GPFS recovery for the failed node has completed before it runs.
-l | --list: Lists all currently expelled nodes.
-r | --reset: Allows the specified nodes to rejoin the cluster (that is, resets the status of the nodes). To unexpel all of the expelled nodes, issue: mmexpelnode -r -N all.
-N {all | Node[,Node...]}: Specifies a list of host names or IP addresses that represent the nodes to be expelled or unexpelled. Specify the daemon interface host names or IP addresses as shown by the mmlscluster command. The mmexpelnode command does not support administration node names or node classes.
Note: -N all can only be used to unexpel nodes.

Examples of the mmexpelnode command

To expel node c100c1rp3, issue the command:
```
mmexpelnode -N c100c1rp3
```

To show a list of expelled nodes, issue the command:

mmexpelnode --list

The system displays information similar to:

Node List
---------------------
    192.168.100.35 (c100c1rp3.ppd.pok.ibm.com)

To allow node c100c1rp3 to rejoin the cluster, issue the command:
```
mmexpelnode -r -N c100c1rp3
```