IBM General Parallel File System for AIX: Administration and Programming Reference

Adding nodes to your GPFS nodeset

You can add nodes to an existing GPFS nodeset issuing the mmaddnode command. You must follow these rules when adding nodes:

• A node may belong to only one nodeset at a time.
• If multi-node quorum has been specified for the nodeset, the existing nodeset must meet quorum for the nodes to be added. For example, if GPFS is currently configured on eight nodes, all of which are up and running, the quorum value is met and the new nodes join the nodeset. Conversely, if GPFS is currently configured on eight nodes and only four are up and running, a quorum of five does not exists and the new nodes may not join the nodeset. When five of the original eight nodes are up and running, the new nodes are added.

  After the nodes have been added and GPFS is started on the new nodes, the quorum value for the nodeset is adjusted accordingly. This allows new nodes to join a running nodeset without causing quorum to be lost. You must start GPFS manually the first time it is started on the new nodes by issuing the mmstartup command.

  When adding nodes to a nodeset using the single-node quorum algorithm, the GPFS daemon must be stopped on all of the nodes. If after adding the nodes, the number of nodes in the nodeset exceeds two, the quorum algorithm is automatically changed to the multi-node quorum algorithm.

For example, to add node k145n08 to nodeset set1, enter:

mmaddnode -C set1 k145n08

To confirm the addition, enter:

mmlsnode -C set1

The system displays information similar to:

GPFS nodeset    Node list
-------------   -------------------------------------------------------
   set1         k145n08 k145n29 k145n30 k145n31 k145n32
 

See the mmaddnode Command for complete usage information.

Note:

You must start GPFS manually the first time it is started on the new nodes by issuing the mmstartup command.