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Host redundancy lost

A Host is unable to communicate with one of the storage array's controllers.

This problem occurs for the following reasons:

  • The host is only connected to one of the storage array's controllers.

  • A Small Form-Factor Pluggable (SFP) transceiver has failed.

  • A loose, damaged, or disconnected cable exists between the affected host and controller.

  • A Hub or Fabric switch connecting the affected host and controller is not functioning properly.

  • The host's host adapter has failed.

Important

  • As the host is unable to communicate with both of the storage array's controllers, some volumes assigned to the affected host may also be reporting a Volume Not on Preferred Path problem as a result of this problem.

  • Disabling the automatic load balancing feature will cause the storage array to stop reporting this problem.

Recovery Steps​

  1. Is the host shown in the Details area only connected to one of the storage array's controllers?

    • If yes, go to step 2.

    • If no, go to step 5.

  2. Is the host's configuration approved to only connect to a single controller?

    • If yes, go to step 3.

    • If no, go to step 4.

  3. Disable the automatic load balancing feature, and go to step 16.

    1. Go to Settings > System.

    2. Select the Enable/Disable Automatic Load Balancing link in the Additional Settings section and disable Automatic Load Balancing on the storage array.

    3. Go to step 16.

  4. Connect the host to the affected controller according to the applicable Express Guide for your host's OS and I/O interface type, and then go to step 15.

  5. Are any SFP Failed problems being reported in the Problems area?

    • If yes, replace the failed SFP using the recovery steps in the SFP Failed procedure listed in the Problems area. Then, go to step 15.

    • If no, go to step 6.

  6. Are there any loose, damaged, or disconnected cables between the host and controller shown in the Details area?

    • If yes, fix the problem, and then go to step 15.

    • If no, go to step 7.

  7. Is the host connected to the storage array through one or more switches?

    • If yes, go to step 8.

    • If no, go to step 10.

  8. Does the switches connecting the host and storage array show any indications of a faulty port, SFP, or other failure?

    • If yes, correct the problem, and then go to step 15.

    • If no, go to step 9.

  9. Are the controller and host connected to the correct switches and switch zones?

    • If yes, go to step 10.

    • If no, correct the problem, and then go to step 15.

  10. Is the host connected to the storage array via iSCSI or Infiniband?

    • If yes, go to step 11.

    • If no, go to step 12.

  11. Is the host and affected controller's host ports and network sessions properly configured according to the applicable Express Guide for your host's OS and I/O interface type?

    • If yes, go to step 12.

    • If no, fix the problem and then go to step 15.

  12. Are volumes from any other storage arrays assigned to the affected host?

    • If yes, go to step 13.

    • If no, go to step 14.

  13. Check the status of the other storage arrays that have volumes assigned to the host.

    1. Open the system manager for the storage arrays.

    2. Check to see if the storage array is optimal.

    Are any of the storage arrays that the affected host is connected to Optimal?

    • If yes, contact your Technical Support Engineer.

    • If no, the host's host adaptor is most likely faulty. Fix any problems with the host adapter, and then go to step 15.

  14. Is the host's host adapter operational?

    • If yes, contact your Technical Support Engineer.

    • If no, correct the problem, then go to step 15.

  15. Redistribute all volumes back to their preferred owner.

    1. Go to Storage > Volumes.

    2. Select Redistribute volumes under More.

  16. Wait 10 minutes, and then select Recheck to ensure the problem has been resolved.