Expansion Enclosure - Loss of Path Redundancy

What Caused the Problem?

An expansion enclosure with redundant channels has lost redundancy and has only one channel available for I/O. The Recovery Guru Details area provides specific information you will need as you follow the recovery steps.

Loss of path redundancy can result from any of the following:

Removed or faulty EMM module (a separate problem should be reported)
Removed or faulty RAID controller module on an enclosure (a separate problem should be reported)
Disconnected or faulty cables
Improperly seated EMM module

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

Important Notes

Correct this failure as soon as possible. Although the storage array is still operational, a level of path redundancy has been lost. If the remaining channel fails, all I/O to that expansion enclosure will fail.
The Recovery Guru will report separate problems for any expansion enclosures it cannot reach through the channel of the affected enclosure.
The Recovery Guru Details area reports the affected expansion enclosure and the WORKING channel over which it can communicate with the expansion enclosure.
The status LED on the EMM module will be off if the module is not seated properly.

Recovery Steps

Fix any other problems reported by the Recovery Guru before attempting to fix this problem.

If...

Then...

One of the RAID controller modules is removed

Reinsert the RAID controller module.

Go to step 6.

Both RAID controller modules are present

Identify the EMM module in the expansion enclosure that is reporting the failure condition.

Go to step 3.

Check for loose or damaged cables. If there are cable issues, the EMM module status LED may be OFF.

If...	Then...
There is a connection problem	Correct it and go to step 6.
There is NOT a connection problem	Go to step 4.

Caution: Possible loss of data accessibility. Do not disconnect any cables on the working channel. Doing so may cause a possible loss of data accessibility.

Click the Recheck button to rerun the Recovery Guru.

If...	Then...
The problem has been fixed	You are finished with this procedure.
The problem has not been fixed	Go to step 5.

If the EMM module status LED is off on either EMM, reseat the EMM module by removing it from the expansion enclosure and waiting 10 seconds. Re-insert the module firmly, then go to step 6.

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.

Note: Additional information on this issue may be available. Please visit the Dell support website at support.dell.com and select your product model. Choose "troubleshooting" as your tool option, then search by this procedure title.