MAP 3253
Use this MAP to resolve the following problem: Multipath redundancy level got worse (SRN nnnn - 4060) for a PCIe3 controller.
The possible
causes follow:
- A failed connection caused by a failing component in the 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.
- A failed connection caused by a failing component between two
SAS adapters, including the AA-cable or the SAS adapters themselves.Note: To view all the paths between two SAS adapters, it might be necessary to use the Show Fabric Path Data view instead of the Show Fabric Path Graphical view.
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 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 and a failed connection can be the result of a failed system board or integrated device enclosure.
- When using SAS adapters in either a high availability (HA) two-system RAID or HA single-system RAID configuration, ensure that the actions taken in this MAP are against the primary adapter and not the secondary adapter.
- Before completing the system verification action in this map, reconstruct any degraded disk arrays if possible. This action helps to avoid the potential data loss that might result from the adapter being reset during system verification action taken in this map.
Attention: When SAS fabric problems exist, obtain
assistance from your hardware service provider before performing any
of the following actions:
- Obtain assistance before you replace a RAID adapter because the adapter might contain nonvolatile write cache data and configuration data for the attached disk arrays, additional problems might be created by replacing an adapter.
- Obtain assistance before you remove functioning disks in a disk array because the disk array might become degraded or might fail, and additional problems might be created if functioning disks are removed from a disk array.
Step 3253-1
Determine whether the problem still exists for the adapter that logged this error by examining the SAS connections as follows:
- Start the IBM® SAS Disk Array Manager.
- Start Diagnostics and select Task Selection on the Function Selection display.
- Select .
- Select .
Do all expected devices appear in the list and are all paths marked as Operational?
- No
- Go to Step 3253-2.
- Yes
- Go to Step 3253-6.
Step 3253-2
Run diagnostics in system verification mode on the adapter to rediscover the devices and connections.
- Start Diagnostics and select Task Selection on the Function Selection display.
- Select Run Diagnostics.
- Select the adapter resource.
- Select System Verification.
Note: Disregard any trouble found for now, and continue with
the next step.
Step 3253-3
Determine whether the problem still exists for the adapter that logged this error by examining the SAS connections as follows:
- Start the IBM SAS Disk Array Manager.
- Start Diagnostics and select Task Selection on the Function Selection display.
- Select .
- Select
- Select Show Fabric Path Graphical View.
- Select a device with a path that is not marked as Operational, if one exists, to obtain additional details about the full path from the adapter port to the device. See Viewing SAS fabric path information for an example of how this additional detail can be used to help isolate where in the path the problem exists.
Do all expected devices appear in the list and are all paths marked as Operational?
- No
- Go to Step 3253-4.
- Yes
- Go to Step 3253-6.
Step 3253-4
Because the problem persists, some corrective action is needed to resolve the problem. Proceed by doing the following steps:
- Power off the system or logical partition.
- Perform only one of the following corrective actions, which are
listed in the order of preference. If one of the corrective actions
was previously attempted, then proceed to the next one in the list.
Note: Prior to replacing parts, consider using a complete powered-down of the entire system, including any external device enclosures, to provide a reset of all possible failing components. This action might correct the problem without replacing parts.
- Reseat the cables on the adapter, on the device enclosure, and between cascaded enclosures if present.
- Replace the cable from the adapter to the device enclosure, and between cascaded enclosures if present.
- Replace the device. Note: If multiple devices have a path which is not marked as Operational, the problem is not likely to be with a device.
- Replace the internal device enclosure, or see the service documentation for an external expansion drawer.
- Replace the adapter.
- Contact your hardware service provider.
- Power on the system or logical partition. Note: In some situations, it might be acceptable to unconfigure and reconfigure the adapter instead of powering off and powering on the system or logical partition.
Step 3253-5
Determine whether the problem still exists for the adapter that logged this error by examining the SAS connections as follows:
- Start the IBM SAS Disk Array Manager.
- Start Diagnostics and select Task Selection on the Function Selection display.
- Select .
- Select .
- Select a device with a path which is not marked as Operational, if one exists, to obtain additional details about the full path from the adapter port to the device. See Viewing SAS fabric path information for an example of how this additional detail can be used to help isolate where in the path the problem exists.
Do all expected devices appear in the list and are all paths marked as Operational?
- No
- Go to Step 3253-4.
- Yes
- Go to Step 3253-6.