5.1.5 How to Disable a Cluster Transport Cable

You might need to disable a cluster transport cable to temporarily shut down a cluster interconnect path. This is useful when troubleshooting a cluster interconnect problem or when replacing cluster interconnect hardware.

When a cable is disabled, the two endpoints of the cable remain configured. An adapter cannot be removed if it is still in use as an endpoint in a transport cable.

A cluster node needs at least one functioning cable attached to the cluster interconnect to be a member of the cluster. Always verify the status of a node's cluster interconnect before disabling a cable. Only disable a cable connection after you have verified that it is redundant; that is, that another connection is available. Disabling a node's last remaining working cable takes the node out of cluster membership.

1. Become superuser on any node in the cluster.

2. Check the status of the cluster interconnect before disabling a cable.

   # scstat -W

   ---

   Caution -

   If you receive an error such as "path faulted" while attempting to remove one node of a two-node cluster, investigate the problem before continuing with this procedure. Such a problem could indicate that a node path is unavailable. Removing the remaining good path takes the node out of cluster membership and could result in a cluster reconfiguration.

   ---

3. Enter the scsetup utility.

   # scsetup

   The Main Menu appears.

4. Access the Cluster Interconnect Menu by entering 2 (Cluster interconnect).

5. Disable the cable by entering 8 (Disable a transport cable).

   Follow the instructions and enter the requested information. All of the components on this cluster interconnect will be disabled. You need to enter both the node and the adapter names of one of the endpoints of the cable you are trying to identify.

6. Verify that the cable is disabled.

   # scconf -p | grep cable

5.1.5.1 Example--Disabling a Cluster Transport Cable

This example shows how to disable a cluster transport cable on adapter qfe-1 located on the node phys-schost-2.

[Become superuser on any node.]
[Enter the scsetup utility:]
# scsetup
[Enter option 8:]
*** Cluster Interconnect Menu ***
    Please select from one of the following options:
    ...
      8) Disable a transport cable
    ...
    Option: 8
[Enter the requested information:]
>>> Disable a Cluster Transport Cable <<<
    ...
    Is it okay to continue (yes/no) [yes]? <Return>
    ...
    To which node is the cable attached? phys-schhost-2
    Name of the adapter on "phys-schost-2"? qfe-1
    Is it okay to proceed with the update (yes/no) [yes]? <Return>

scconf -c -m endpoint=phys-schost-2:qfe1,state=disabled

    Command completed successfully.
    Hit ENTER to continue: <Return>
[Verify that the cable is disabled:]
# scconf -p | grep cable
  Transport cable:   phys-schost-2:qfe1@0 ethernet-1@2    Disabled
  Transport cable:   phys-schost-3:qfe0@1 ethernet-1@3    Enabled
  Transport cable:   phys-schost-1:qfe0@0 ethernet-1@1    Enabled