Problem: Sas Cabling Not Valid; Problem: New Expansion Enclosure Not Detected; Problem: Mirrored Volume Copies No Longer; Identical - IBM Storwize V7000 Troubleshooting And Maintenance Manual

v After the node has been used in a cluster, the node canister has saved information that can identify
whether the canister has been moved to a different enclosure or a different slot in the same enclosure
from where it was previously used. Moving a node canister might compromise its access to storage or
access to volumes by a host application. Do not move the canister from its original location unless
directed to do so by a service action.

Problem: SAS cabling not valid

This topic provides information to be aware of if you receive errors that indicate the SAS cabling is not
valid.
Check the following items:
v No more than five expansion enclosures can be chained to port 1 (below the control enclosure). The
connecting sequence from port 1 of the node canister is called chain 1.
v No more than four expansion enclosures can be chained to port 2 (above the control enclosure). The
connecting sequence from port 2 of the node canister is called chain 2.
v Do not connect a SAS cable between a port on an upper canister and a port on a lower canister.
v In any enclosure, the same ports must be used on both canisters.
v No expansion canister should have a cable attached to SAS port 2 but not SAS port 1.
v For any enclosure, the cables that are connected to SAS port 1 on each canister must attach to the same
enclosure. Similarly, for any enclosure, the cables that are connected to SAS port 2 on each canister
must attach to the same enclosure. Cable attachments for SAS port 1 and cable attachments for SAS
port 2 do not go to the same enclosure.
v For cables connected between expansion enclosures, one end is connected to port 1 while the other end
is connected to port 2.
v For cables that are connected between a control enclosure and expansion enclosures, port 1 must be
used on the expansion enclosures.
v The last enclosure in a chain must not have cables in port 2 of canister 1 and port 2 of canister 2.
v Ensure that each SAS cable is fully inserted.

Problem: New expansion enclosure not detected

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This topic helps you resolve why a newly installed expansion enclosure was not detected by the system.
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When installing a new expansion enclosure, follow the management GUI Add Enclosure wizard, which is
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available from the Manage Devices Actions menu.
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If the expansion enclosure is not detected, perform the following verifications:
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v Verify the status of the LEDs at the back of the expansion enclosure. At least one power supply unit
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4 must be on with no faults shown. At least one canister must be active, with no fault LED on, and all
the SAS port 1 LEDs must be on. For details about the LED status, see "Procedure: Understanding the
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system status using the LEDs" on page 42.
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4 v Verify that the SAS cabling to the expansion enclosure has been correctly installed. To review the
requirements, see "Problem: SAS cabling not valid."
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Problem: Mirrored volume copies no longer identical
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4 The management GUI provides options to either check copies that are identical or to check that the
copies are identical and to process any differences that are found.
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4 To confirm that the two copies of a mirrored volume are still identical, choose the volume view that
works best for you. Select one of the volume copies in the volume that you want to check. From the
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Actions menu, select the Validate Volume Copies option.
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Chapter 5. Resolving a problem
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