This procedure is used to resolve the following problems:
- Multipath redundancy level is worse (SRC xxxx4060)
- Device bus fabric error (SRC xxxx4100)
- Temporary device bus fabric error (SRC xxxx4101)
The possible causes are:
- A failed connection caused by a failing component in the serial
attached SCSI (SAS) fabric between, and including, the adapter and
device enclosure.
- A failed connection caused by a failing component within the device
enclosure, including the device itself.
Note: For SRC xxxx4060, the failed connection was previously
working, and might have already recovered.
Considerations:
- Power off the system, partition, or card slot before connecting
and disconnecting cables or devices, as appropriate, to prevent hardware
damage.
- Some systems have the disk enclosure or removable media enclosure
integrated in the system with no cables. For these configurations,
the SAS connections are integrated onto the system boards. A failed
connection can be the result of a failed system board or integrated
device enclosure.
- Some systems have SAS RAID adapters integrated onto the system
backplane and use a cache RAID and dual IOA enablement card to enable
storage adapter write cache and dual storage I/O adapter (IOA) mode.
For these configurations, replacement of the cache RAID and dual IOA
enablement card is unlikely to solve a SAS-related problem because
the SAS interface logic is on the system backplane.
- When using SAS adapters in a dual storage IOA configuration, ensure
that the actions taken in this procedure are against the primary adapter
(not the secondary adapter).
Attention: - When SAS fabric problems exist, do not replace RAID adapters without
assistance from your service provider. Because the adapter might contain
nonvolatile write cache data and configuration data for the attached
disk arrays, additional problems can be created by replacing an adapter.
- Follow appropriate service procedures when replacing the Cache
RAID and dual IOA enablement card. Incorrect removal can result in
data loss or a nondual storage IOA mode of operation.
- Do not remove functioning disk units in a disk array without assistance
from your service provider. A disk array might become unprotected
or might fail if functioning disk units are removed. The removal of
functioning disk units might also result in additional problems in
the disk array.