Dell EMC PowerVault MD 34XX/38XX Series Storage Arrays Administrator's Guide

Recovering from unresponsive storage array condition

A storage array can have an Unresponsive status for several reasons. Use the procedure in this topic to determine a possible cause and solution. The MD Storage Manager can take up to five minutes to detect that a storage array has become unresponsive or becomes responsive again. Before completing this procedure, make sure that you wait for some time before you decide that the storage array is still unresponsive.

1. Check the Tree View in the EMW to see if all storage arrays are unresponsive.
2. If any storage arrays are unresponsive, check the storage management station network connection to make sure that it can reach the network.
3. Ensure that the RAID controller modules are installed and that there is power to the storage array.
4. If there a problem with the storage array, then correct the problem.
5. Perform one of these actions, depending on how your storage array is managed:
   • Out-of-band managed storage array—Go to step 6.
   • In-band managed storage array—Go to step 12.
6. For an out-of-band managed storage array, ensure that the RAID controller modules are network accessible by using the ping command to make sure that the RAID controller module can be reached. Type one of these commands, and press <Enter>.
   • ping <host-name>
   • ping <RAID controller module-IP-addres>
7. If the verification is successful, see step 8, if not, see step 9.
8. Remove the storage array with the Unresponsive status from the EMW, and select Add Storage Array to add the storage array again.
9. If the storage array does not return to Optimal status, check the Ethernet cables to make sure that there is no visible damage and that they are securely connected.
10. Make sure the appropriate network configuration tasks have been performed. For example, make sure that IP addresses have been assigned to each RAID controller module.
11. If there is a cable or network accessibility problem, see step 20, if not step 12.
12. For an in-band managed storage array, make sure that the host is network accessible by using the ping command to verify that the host can be reached. Type one of these commands, and press <Enter>.
    • ping <host-name>
    • ping <RAID controller module-IP-addres>
13. If the verification is successful, see step 14, if not, step 15.
14. Remove the host with the Unresponsive status from the EMW, and select Add Storage Array to add the host again.
15. If the host does not return to Optimal status, go to step 16.
16. Ensure that the host is turned on and operational and that the host adapters have been installed.
17. Check all external cables and switches or hubs to make sure that no visible damage exists and that they are securely connected.
18. Make sure the Host Context Agent software is installed and running.
    If you started the host system before you were connected to the RAID controller module in the storage array, the Host Context Agent software will not be able to detect the RAID controller modules. If so, make sure that the connections are secure, and restart the Host Context Agent software.
19. If you have recently replaced or added the RAID controller module, restart the Host Context Agent software so that the new RAID controller module is recognized.
20. If the problem still exists, make the appropriate host modifications, check with other administrators to see if a firmware upgrade was performed on the RAID controller module from another storage management station.
    If a firmware upgrade was performed, the EMW on your management station may not be able to locate the new AMW software needed to manage the storage array with the new version of the firmware.
21. If the problem persists contact your Technical Support representative.
22. Determine if there is an excessive amount of network traffic to one or more RAID controller modules.
    This problem is self-correcting because the EMW software periodically retries to establish communication with the RAID controller modules in the storage array. If the storage array was unresponsive and a subsequent attempt to connect to the storage array succeeds, the storage array becomes responsive.

    For an out-of-band managed storage array, determine if management operations are taking place on the storage array from other storage management stations. A RAID controller module-determined limit exists to the number of Transmission Control Protocol/Internet Protocol (TCP/IP) connections that can be made to the RAID controller module before it stops responding to subsequent connection attempts. The type of management operations being performed and the number of management sessions taking place together determine the number of TCP/IP connections made to a RAID controller module. This problem is self-correcting because, after some TCP/IP connections terminate, the RAID controller module then becomes responsive to other connection attempts.

23. If the storage array is still unresponsive, a problem may exist with the RAID controller modules. Contact your Technical Support representative.