Use the following
to perform SAS fabric problem isolation.
Considerations:
- Remove power from the system before connecting and disconnecting
cables or devices, as appropriate, to prevent hardware damage or erroneous
diagnostic results.
- Some systems have SAS and PCI-X bus interface logic integrated
onto the system boards and use a pluggable RAID Enablement Card (a
non-PCI form factor card) for these SAS/PCI-X buses. For these configurations,
replacement of the RAID Enablement Card is unlikely to solve a SAS
fabric-related problem because the SAS interface logic is on the system
board.
Attention: Replacing RAID adapters is not recommended
without assistance from your service support organization when SAS
fabric problems exist. Because the adapter may contain non-volatile
write cache data and configuration data for the attached disk arrays,
additional problems can be created by replacing an adapter when SAS
fabric problems exist.
Attention: Removing functioning
disks in a disk array is not recommended without assistance from your
service support organization. A disk array may become Degraded or Failed if
functioning disks are removed. Also, additional problems may be created.
Identify the SAS fabric on which the problem is occurring
by examining the error log entry.
Go to Step 3350–2.
Step 3350–2
Have changes
been made to the SAS configuration recently?
NO Go
to Step 3350–5.
YES Go
to Step 3350–3.
Step 3350–3
Check for the
following problems:
- Cabling problems such as configurations that exceed the maximum
cable lengths
- Ensure the SAS configuration does not have multi-initiators (for
example, set up for a high-availability configuration)
Note: Multi-initiator support is not provided at this time.
For
more details about supported SAS cabling, refer to RS/6000 pSeries
Adapters, Devices, and Cable Information for Multiple Bus Systems.
Did you find a problem?
NO Go to Step 3350–5.
YES Go
to Step 3350–4.
Step 3350–4
- Power off the system or logical partition.
- Correct the problem.
- Power on the system or logical partition. If you cannot power
on normally, boot to Rescue mode. Examine the error log.
Did a SAS fabric-related failure occur?
NO Go
to Step 3350–14.
YES Go
to Step 3350–5.
Step 3350–5
Determine if
any of the disk arrays on the adapter are in an Degraded state.
For further details, see Viewing array status.
Does
any disk array have a state of Degraded ?
NO Go
to Step 3350–7.
YES Go
to Step 3350–6.
Step 3350–6
- Identify the failed disks by first finding disk arrays with
a state of Degraded , then finding disks on those arrays with
a state of Failed.
- Remove the failed disks from each Degraded disk array.
For further details, see Physical disks.
- Reboot the system or logical partition. If you cannot power on
normally, boot to Rescue mode. Examine the error log.
Did a SAS fabric related failure occur?
NO Go
to Step 3350–14.
YES Go
to Step 3350–7.
Step 3350–7
Are there any
non-essential removable media devices (such as Tape, CDROM, and DVDROM)
on the SAS fabric?
NO Go to Step 3350–10.
YES Go
to Step 3350–8.
Step 3350–8
- Power off the system or logical partition.
- Remove one of the non-essential removable media devices.
- Power on the system or logical partition. If you cannot power
on normally, boot to Rescue mode. Examine the error log.
Did a SAS fabric related failure occur?
NO Go
to Step 3350–9.
YES Go
to Step 3350–7.
Step 3350–9
The last removable
media device removed from the SAS fabric may be the cause of the SAS
fabric problems. Follow the repair procedures for that device.
Go
to Step 3350–14.
Step 3350–10
Are there
any non-essential disks that are not disk array members (such as 512
byte/sector JBOD disks, Hot Spare disks, or Advanced
Function disks) on the SAS fabric?
NO Go to Step 3350–13.
YES Go
to Step 3350–11.
Step 3350–11
- Remove one of the non-essential disk devices. For further details,
see Physical disks.
- Reboot the system or logical partition. If you cannot power on
normally, boot to Rescue mode. Examine the error log.
Did a SAS fabric related failure occur?
NO Go
to Step 3350–12.
YES Go
to Step 3350–10.
Step 3350–12
The last disk
removed from the SAS fabric may be the cause of the SAS fabric problems.
Follow the repair procedures for that device.
Go to Step 3350–14.
Step 3350–13
Contact your
service support organization.
Exit this procedure
Step 3350–14
- Reinstall any good devices that were removed during the course
of this MAP.
- Reboot the system or logical partition. If you cannot power on
normally, boot to Rescue mode. Examine the error log.
- Take action on any other non-SAS fabric related errors if they
exist.
Subscribe to this information