SIP3144

Use this procedure to resolve problems with multipath connections.

About this task

This procedure is used to resolve the following configuration errors:

  • Configuration error, incorrect multipath connection (SRC xxxx4030)
  • Configuration error, incomplete multipath connection between adapter and enclosure detected (SRC xxxx4040)
The possible causes are:
  • Incorrect cabling to device enclosure.
    Note: Pay special attention to the requirement that a Y0-cable, YI-cable, or X-cable must be routed along the right side of the rack frame (as viewed from the rear) when connecting it to a disk expansion unit. Review the device enclosure cabling and correct the cabling as required. To see example device configurations with serial attached SCSI (SAS) cabling, see Serial-attached SCSI cable planning, in the Site and hardware planning.
  • A failed connection caused by a failing component in the SAS fabric between, and including, the adapter and device enclosure.
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 and 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.
  • Some configurations involve a SAS adapter connecting to internal SAS disk enclosures within a system using a cable card. Keep in mind that when the procedure refers to a device enclosure, it could be referring to the internal SAS disk slots or media slots. Also, when the procedure refers to a cable, it could include a cable card.
  • When using SAS adapters in a dual storage IOA configuration, ensure that the actions taken in this procedure are against the primary adapter (that is, 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 non-volatile 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.

Procedure

  1. Was the SRC xxxx4030?
    No:
    Go to step 5.
    Yes:
    Go to step 2.
  2. Identify the affected adapter and its port by examining the product activity log. Perform the following steps:
    1. Access SST or DST.
    2. Access the product activity log and record address information.
      If a type D IPL was not performed to get to SST or DST:
      The log information is formatted. Access the product activity log and display the SRC that sent you here. Press the F9 key for address information. This is the adapter address. Then, press F12 to cancel and return to the previous screen. Then press the F4 key to view the additional information to record the formatted log information. The Adapter Port field indicates the port on the adapter reporting the problem. There may be more than one port listed because multiple ports map to the same physical connector. For example, ports 0 through 3 map to the first physical connector, 4 through 7 map to the second physical connector, and so on. The port numbers are labeled on the adapter tailstock.
      If a type D IPL was performed to get to DST:
      The log information is not formatted. Access the product activity log and display the SRC that sent you here. The direct select address (DSA) of the adapter is in the format BBBB-xxxx:
      BBBB
      Hexadecimal offsets 4C and 4D
      xxxx
      Not used

      In order to interpret the hexadecimal information to get device addresses, see Examples: Obtaining additional information from hexadecimal reports. The Adapter Port field indicates the port on the adapter reporting the problem. There may be more than one port listed because multiple ports map to the same physical connector. For example, ports 0 through 3 map to the first physical connector, 4 through 7 map to the second physical connector, and so on. The port numbers are labeled on the adapter tailstock.

    3. Determine the location of the adapter that reported the problem.
      Go to Addresses and find the following items:
      • The card slot that is identified by the direct select address (DSA)
      • The physical connector identified by the port number found on the adapter tailstock
      Have you determined the location of the adapter and its port?
      • No: Ask your next level of support for assistance. This ends the procedure.
      • Yes: Continue with the next step.
  3. Review the device enclosure cabling and correct the cabling as required for the device or device enclosure attached to the identified adapter port. To see example device configurations with SAS cabling, see Serial-attached SCSI cable planning, in the Site and hardware planning information.
  4. Perform the following steps to cause the adapter to rediscover the devices and connections:
    Note: Performing this step causes the system partition to temporarily hang. Wait until the system bypasses the temporary hang.
    1. Use the logical resources I/O debug option in Hardware Service Manager to perform another IPL of the virtual I/O processor that is associated with this adapter.
    2. Vary on any other resources attached to the virtual I/O processor.
    Did the error recur?
    No:
    This ends the procedure.
    Yes:
    Contact your hardware service provider. This ends the procedure.
  5. The SRC is xxxx4040. Determine whether a problem still exists for the DCxx adapter resource that logged this error by examining the SAS connections. See Viewing SAS fabric path information.
    Do all expected devices appear in the list and are all paths marked as Operational?
    • No: Continue with the next step.
    • Yes: The error condition no longer exists. This ends the procedure.
  6. Perform the following steps to cause the adapter to rediscover the devices and connections:
    1. Use Hardware Service Manager to re-IPL the virtual I/O processor that is associated with this adapter.
    2. Vary on any other resources attached to the virtual I/O processor.
    Note: At this point, ignore any problems found and continue with the next step.
  7. Determine if the problem still exists for the adapter that logged this error by examining the SAS connections by performing the actions in step 5 again.
    Do all expected devices appear in the list and are all paths marked as Operational?
    No
    Go to step 8.
    Yes
    This ends the procedure.
  8. Because the problem persists, some corrective action is needed to resolve the problem. Proceed by doing the following:

    Perform only one of the following corrective actions (listed in the order of preference). If one of the corrective actions has previously been attempted, proceed to the next one in the list.

    • Reseat cables if present on adapter and device enclosure. Perform the following:
      1. Use adapter concurrent maintenance to power off the adapter slot, or power off the system or partition.
      2. Reseat the cables.
      3. Use adapter concurrent maintenance to power on the adapter slot, or power on the system or partition.
    • Replace the cable, if present, from the adapter to the device enclosure. Perform the following steps:
      1. Use adapter concurrent maintenance to power off the adapter slot, or power off the system or partition.
      2. Replace the cables.
      3. Use adapter concurrent maintenance to power on the adapter slot, or power on the system or partition.
    • Replace the internal device enclosure parts or see the service documentation for an attached external device enclosure to identify the parts to replace in the SAS path. Perform the following steps:
      1. If the enclosure is external, adapter concurrent maintenance or enclosure concurrent maintenance procedures can be used to power off the adapter slot. Otherwise, power off the system or partition.
      2. Replace the device enclosure parts.
      3. If the enclosure is external, use adapter concurrent maintenance to power on the adapter slot. Otherwise, power on the system or partition.
    • Replace the adapter. The procedure to replace the adapter can be found in Adapters.
    • Contact your service provider.
  9. To determine if the problem still exists for the adapter that logged this error, examine the SAS connections by performing the actions in step 5 again.
    Do all expected devices appear in the list and are all paths marked as Operational?
    No:
    Go to step 8.
    Yes:
    This ends the procedure.