Data Domain: Filesystem Failure Due to Incorrect DS60 Power Cabling

• Filesystem became unavailable due to missing external storage enclosures/disks (caused by power outage)..
• Disks reported as absent.
• Alerts logged:

  • Event ID: EVT-STORAGE-00002
    Message: Unable to access a disk and the disk state is absent

  • Event ID: EVT-FILESYS-00002
    Message: Problem is preventing filesystem from running.

• The DS60 power has been incorrectly cabled inside the customer rack.

Data Domain systems are designed for fault tolerance with two independent AC power feeds (N+1). If one PDU fails, the system should remain operational.

However, DS60 shelves have:

• Two PSUs per shelf, each with two AC inlets (total: Four AC connections per shelf)
• Proper cabling requires:
  • Each PSU connected to a separate PDU
  • PDUs connected to independent UPS sources

If both AC inlets of a PSU are connected to the same PDU, losing that PDU leaves only one feed per PSU, causing the DS60 shelf to shut down and the filesystem to fail.

Note: Dell EMC factory-racked systems are correctly cabled and do not exhibit this issue.

Example of Correct Cabling:

To correct cabling without downtime:

1. Refer to the diagram for proper cabling layout.
2. Obtain a spare power cable to swap incorrect connections without removing both cables from a PSU.
3. Engage a Dell EMC engineer to perform the correction safely.