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Loss of a single FC-to-SAS bridge

You can test the failure of a single FC-to-SAS bridge to make sure there is no single point of failure.

This test should take about 15 minutes.

This procedure has the following expected results:

  • Errors should be generated as the bridge is switched off.

  • No failover or loss of service should occur.

  • Only one path from the controller module to the drives behind the bridge is available.

  1. Turn off the power supplies of the bridge.
  2. Confirm that the bridge monitoring indicates an error: storage bridge show 

    cluster_A::> storage bridge show

                                                                Is        Monitor
    Bridge     Symbolic Name Vendor  Model     Bridge WWN       Monitored Status
    ---------- ------------- ------- --------- ---------------- --------- -------
    ATTO_10.65.57.145
         bridge_A_1    Atto    FibreBridge 6500N
                                               200000108662d46c true      error
  3. Confirm that drives behind the bridge are available with a single path: storage disk error show 

    cluster_A::> storage disk error show
    Disk             Error Type        Error Text
    ---------------- ----------------- --------------------------------------------
    1.0.0            onedomain         1.0.0 (5000cca057729118): All paths to this array LUN are connected to the same fault domain. This is a single point of failure.
    1.0.1            onedomain         1.0.1 (5000cca057727364): All paths to this array LUN are connected to the same fault domain. This is a single point of failure.
    1.0.2            onedomain         1.0.2 (5000cca05772e9d4): All paths to this array LUN are connected to the same fault domain. This is a single point of failure.
    ...
    1.0.23           onedomain         1.0.23 (5000cca05772e9d4): All paths to this array LUN are connected to the same fault domain. This is a single point of failure.