Adding nodes to a GPFS cluster

Assumption:

1. You have to exchange SSH keys between GPFS nodes and Servers. For more information on key exchange, you can take a look at Auto SSH Login without Password
2. You have installed the gpfs packages. See Installing GPFS 3.4 Packages

You must follow these rules when adding nodes to a GPFS cluster:

• You may issue the command only from a node that already belongs to the GPFS cluster.
• A node may belong to only one GPFS cluster at a time.
• The nodes must be available for the command to be successful. If any of the nodes listed are not available when the command is issued, a message listing those nodes is displayed. You must correct the problem on each node and reissue the command to add those nodes.
• After the nodes are added to the cluster, you must use the mmchlicense command to designate appropriate GPFS licenses to the new nodes.

To add node2 to the GPFS cluster, enter:

# mmaddnode -N node2
The system displays information similar to:
Mon Aug 9 21:53:30 EDT 2004: 6027-1664 mmaddnode: Processing node2

mmaddnode: Command successfully completed
mmaddnode: 6027-1371 Propagating the changes to all affected nodes.
This is an asynchronous process.

To confirm the addition of the nodes, enter:

# mmlscluster

The system displays information similar to:

GPFS cluster information
========================
  GPFS cluster name:         gpfs_cluster
  GPFS cluster id:           680681562214606028
  GPFS UID domain:           gpfs_cluster.com
  Remote shell command:      /usr/bin/rsh
  Remote file copy command:  /usr/bin/rcp

GPFS cluster configuration servers:
-----------------------------------
  Primary server:    nsd1
  Secondary server:  nsd2

 Node  Daemon node name        IP address       Admin node name         Designation
--------------------------------------------------------------------------------------
   1   nsd1                    198.117.68.68      nsd1                  quorum
   2   nsd2                    198.117.68.69      nsd2                  quorum
   3   node2                   198.117.68.70      node2

At the GPFS Clients, remember to add the path in your .bashrc

export PATH=$PATH:/usr/lpp/mmfs/bin

Update the License file of GPFS. Do make sure you have purchased your licenses from IBM. My license file is located at /gpfs_install

# vim /gpfs_install/license_client.lst

node1
node2

Issue the mmchlicense command to set the license nodes in the cluster. Make sure you have purchased the licenses from IBM.

# mmchlicense client --accept -N license_client.lst

node1
node2
mmchlicense: Command successfully completed
mmchlicense: Propagating the cluster configuration data to all affected nodes.  This is an asynchronous process.

Use the mmstartup command to start the GPFS daemons on one or more nodes. If you wish to specify only a node to startup

# mmstartup -N node2

You should see the /dev/gpfs_data mounted on the client node.