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IZ97942: ERROR RECOVERY LOOP IF TARGET LOGS OUT THEN LEAVES SAN APPLIES TO AIX 7100-01

A fix is available

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You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • If the Fibre Channel adapter is attached to a fabric and if
    dynamic tracking or fast_fail is enabled and if a storage
    target explicitly logs out of the host just before leaving
    the SAN fabric, then an endless loop can occur in the Fibre
    Channel driver's error recovery.  The host will continuously
    send queries to the SAN fabric name server to request
    information about the storage port that left the fabric.
    The large number of queries may monopolize traffic on the
    Fibre Channel link, or may overwhelm the fabric name server
    causing broader outages in the SAN.
    

Local fix

Problem summary

  • If the Fibre Channel adapter is attached to a fabric and if
    dynamic tracking or fast_fail is enabled and if a storage
    target explicitly logs out of the host just before leaving
    the SAN fabric, then an endless loop can occur in the Fibre
    Channel driver's error recovery.  The host will continuously
    send queries to the SAN fabric name server to request
    information about the storage port that left the fabric.
    The large number of queries may monopolize traffic on the
    Fibre Channel link, or may overwhelm the fabric name server
    causing broader outages in the SAN.
    

Problem conclusion

  • The loop is broken by setting a flag indicating that a new
    login is needed later, instead of initiating the login right
    away.
    

Temporary fix

Comments

APAR Information

  • APAR number

    IZ97942

  • Reported component name

    AIX V7.1

  • Reported component ID

    5765H4000

  • Reported release

    710

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Submitted date

    2011-04-01

  • Closed date

    2011-04-01

  • Last modified date

    2013-04-16

  • APAR is sysrouted FROM one or more of the following:

    IZ97398

  • APAR is sysrouted TO one or more of the following:

Fix information

  • Fixed component name

    AIX V7.1

  • Fixed component ID

    5765H4000

Applicable component levels

  • R710 PSY U838186

       UP11/10/05 I 1000

PTF to Fileset Mapping

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Document Information

Modified date:
16 April 2013