Dedicated Mirror Channel Failed

What Caused the Problem?

A dedicated cache mirroring channel has failed. The Recovery Guru Details area provides specific information you will need as you follow the Recovery Steps.

 Caution: Electrostatic discharge can damage sensitive components. Always use proper antistatic protection when handling components. Touch components without using a proper ground may damage the equipment.

 Caution: Possible loss of data accessibility. Do not remove a component when either (1) the Service action (removal) allowed (SAA) field in the Details area of this recovery procedure is NO (), or (2) the SAA LED on the affected component is OFF (note that some products do not have SAA LEDs). Removing a component while its SAA LED is OFF may result in temporary loss of access to your data. Refer to the following Important Notes and the Recovery Steps for more detail.

Important Notes

Recovery Steps

Refer to the 'Component requiring service' field in the Details area to determine which procedure you need to complete.

If... Then...
The component that requires service is a controller Go to "Procedure for Replacing a Controller."
The component that requires service field displays "Unknown" The problem cannot be traced to a particular component.  The problem can be with either Controller A, Controller B, or with the Interconnect-Battery Canister.  It is recommended that you contact your technical support representative to assist you with resolving this problem.  Do not continue with the remaining Recovery Steps until instructed to do so by your technical support representative.

Advanced users only:  If you have a spare controller or interconnect-battery canister, you can use the spares to replace the components to determine if the problem is resolved.  Use the steps provided in "Procedure for Replacing a Controller" to replace Controller A first, then Controller B, and then use the steps provided in "Procedure for Replacing an Interconnect-Battery Canister" to replace the Interconnect-Battery canister (if applicable for your model of controller enclosure).  After replacing each component, click the Recheck button in the Recovery Guru to determine if the problem has been fixed.

Procedure for Replacing a Controller

1 If there are any hosts connected to this storage subsystem that are NOT running a host-based, multi-path failover driver, stop I/O to the storage subsystem from each of these hosts.
2 Place the affected controller offline. The affected controller is listed in the 'Component requiring service' field in the Details area.
a Select the controller in the Physical View of the Subsystem Management Window.
b Select Advanced >> Recovery >> Set Controller >> Offline.
c Complete the instructions in the dialog, then select Yes.
3 Read all of the following steps before taking any action. The remaining Recovery Steps will no longer be accessible from the Recovery Guru dialog after you complete step a.
a Click the Recheck button to rerun the Recovery Guru.
b Select the "Offline Controller" problem that is being reported in the Summary area.
c Complete the Recovery Steps in the "Offline Controller" recovery procedure to replace the affected controller.

Procedure for Replacing an Interconnect-Battery Canister

1 Obtain a replacement Interconnect-battery canister with the same part number as the failed one.

Note: The part number of the Interconnect-battery canister can be located in the Storage Subsystem Profile or in the View Enclosure Components dialog.

2 Prepare the Interconnect-battery canister for removal by completing the following steps:
a Select the Advanced >> Troubleshooting >> Prepare for Removal menu option.
b Select the appropriate Enclosure (as listed in the Details area) and then the Interconnect-battery canister from the respective drop-down menus.
c Click the Prepare for Removal button.
d
If... Then...
The resulting dialog indicates that the component is safe to remove Go to step 3.
The resulting dialog indicated that the component is NOT safe to remove Answer the following question:

Are there other problems being reported in the Summary area?

  • Yes - Fix these problems first and then return to this procedure after clicking the Recheck button.
  • No - Stop this procedure and contact your technical support representative
3 Remove the Interconnect-battery canister.
If... Then...
This storage subsystem is configured to operate without batteries Make sure that the new canister does not contain batteries, otherwise the storage subsystem will have a Needs Attention status if it is inserted with batteries.

Go to step 4.

This storage subsystem is configured to operate with batteries
If... Then...
The new canister contains batteries Go to step 4.
The new canister does NOT contain batteries Remove the batteries from the failed canister and insert them into the new canister.

Go to step 4.

4 Insert the new replacement Interconnect-battery canister and be sure that the canister is securely seated.
5 Click the Recheck button to rerun the Recovery Guru. The failure should no longer appear in the Summary area. If the failure appears again, contact your technical support representative.