Recovering a node and returning it to the cluster

After a node or an I/O group fails, you can use the SAN Volume Controller to recover a node and return it to the cluster.

1. Click Work with Nodes > Nodes in the portfolio. The Viewing Nodes panel is displayed.
2. Verify that the node is offline.
3. Select the offline node.
4. Select Delete a Node from the task list and click Go. The Deleting Node from Cluster panel is displayed.
5. Click Yes.
6. Verify that the node can be seen on the fabric.
7. If the nodes are repaired by replacing the front panel module or a node is repaired by replacing it with another node, the worldwide node name (WWNN) for the node changes. In this case, you must follow these additional steps:
   1. At the end of the recovery process, you must follow your multipathing device driver's procedure to discover the new paths and to check that each device identifier is now presenting the correct number of paths. If you are using the subsystem device driver (SDD), the device identifiers are referred to as virtual paths (vpaths). See the IBM System Storage® Multipath Subsystem Device Driver User's Guide or the documentation that is provided with your multipathing device driver for more information.
   2. You might also have to modify the configuration of your disk controller systems. If your disk controller system uses a mapping technique to present its RAID arrays or partitions to the cluster, you must modify the port groups that belong to the cluster because the WWNN or worldwide port names (WWPNs) of the node have changed.
   Attention: If more than one I/O group is affected, ensure that you are adding the node to the same I/O group from which it was removed. Failure to do this can result in data corruption. Use the information that was recorded when the node was originally added to the cluster. This can avoid a possible data corruption exposure if the node must be removed from and re-added to the cluster. If you do not have access to this information, call the IBM® Support Center to add the node back into the cluster without corrupting the data. If you are adding the node into the cluster for the first time, you must record the following information:

   • Node serial number
   • WWNN
   • All WWPNs
   • I/O group that the node belongs to
8. Add the node back into the cluster.
   1. From the Viewing Nodes panel, select Add a Node from the task list and click Go. The Adding a Node to a Cluster panel is displayed.
   2. Select the node from the list of candidate nodes and select the I/O group from the list. Optionally enter a node name for this node.
   3. Click OK.
9. Verify that the node is online by refreshing the Viewing Nodes panel.
   Note: If the panel does not refresh, close the panel and reopen it.