HP XP External Storage Software User Guide (T1706-96018, November 2011)

1. Restore (for example, check the cable's connection status or change the switch) the status of
the error path between the local array and external array 1.
2. Execute the Check Paths & Restore Vol. command using XP External Storage. For instructions,
see Checking the connection status and resuming external LU operations (Check Paths &
Restore Vol.).
3. Change resource group 1's execution node to node 2 using NAS Blade Manager (failover).
If resource group 1's status is Offline, this operation is not required.
4. Stop node 1 using NAS Blade Manager.
5. Restart NAS OS 1 (NAS channel adapter's OS) using XP LUN Configuration and Security
Manager Software or NAS Blade Manager.
6. Start node 1 using NAS Blade Manager.
7. Perform one of the following operations using NAS Blade Manager:
When resource group 1's status is Online, change resource group 1's execution node to
node 1 (failback).
When resource group 1's status is Offline, start resource group 1.
8. Change resource group 2's execution node to node 1 using NAS Blade Manager (failover).
If resource group 2's status is Offline, this operation is not required.
9. Stop node 2 using NAS Blade Manager.
10. Restart NAS OS 2 (NAS channel adapter's OS) using XP LUN Configuration and Security
Manager Software or NAS Blade Manager.
11. Start node 2 using NAS Blade Manager.
12. Perform one of the following operations using NAS Blade Manager:
When resource group 2's status is Online, change resource group 2's execution node to
node 2 (failback).
When resource group 2's status is Offline, start resource group 2.
Errors in all paths to the external array
The following sections describe the recovery procedures for two examples when the error occurs
in all paths connected to the external array.
If each node uses a different external array
If both nodes use the same external array
If each node uses a different external array
In the configuration in Figure 64 (page 125), all of the NAS Blade system's user LUs are volumes
in the external array. Each node uses the volume of a different array. All of node 1's user LUs are
volumes in external array 1. Therefore, if an error occurs in the path between the local array and
external array 1, the error occurs in all paths connected from node 1 to external array 1. In this
situation, no user LU is available for node 1.
The situation in Figure 64 (page 125) is as follows:
The NAS Blade system attempts to change resource group 1's execution node to node 2
because no user LU can be used from node 1 (failover). However, node 2 cannot access
volumes in external array 1, the failover function failed, and an srmd executable error appears
as error information for resource group 1.
The file system's status is blocked on node 2 because of the failure of the failover of resource
group 1.
124 Troubleshooting NAS Blade systems that include external arrays