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IV64633: CHDEV WILL ALWAYS BREAK THE RESERVES ON A LUN. APPLIES TO AIX 7100-02

A fix is available

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APAR status

  • Closed as program error.

Error description

  • chdev will break the reserves on a lun regardless of the
    host
    that owns the lun.  The code attempts to open the lun
    with
    no reserve and if that fails we will break the reserve.
    

Local fix

Problem summary

  • The disk change method currently sends out a LUN reset to
    clear any stale reserves any time that the reserve_policy is
    changed from either no_reserve or single_path to one of the PR
    reserve types.  This occurs even if the "-P" flag is used on
    the chdev command.  This could result in another host's
    reservation being unexpectedly cleared on a shared disk.
    The other host should receive a SCSI unit attention and
    re-establish the reservation.
    

Problem conclusion

  • Modify the SCSI disk change method so that the LUN reset is
    only sent if the local node has access to the disk.  This
    proves that the disk is not reserved by another host, so the
    LUN reset will only clear a stale reserve owned by the local
    host.
    

Temporary fix

Comments

  • 6100-08 - use AIX APAR IV63136
    6100-09 - use AIX APAR IV64621
    7100-02 - use AIX APAR IV64633
    7100-03 - use AIX APAR IV64603
    

APAR Information

  • APAR number

    IV64633

  • Reported component name

    AIX V7.1

  • Reported component ID

    5765H4000

  • Reported release

    710

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Submitted date

    2014-09-05

  • Closed date

    2014-09-05

  • Last modified date

    2015-01-21

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

    IV63136

  • 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 U867245

       UP15/01/19 I 1000

PTF to Fileset Mapping



Document information

More support for: AIX Enterprise Edition

Software version: 710

Operating system(s): AIX

Reference #: IV64633

Modified date: 21 January 2015