PH32595: GM pause causes Freeze on Metro leg

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• In multi-target MGM configurations where Metro and GM secondary
  LSS have the same SSID, a Global Mirror Pause may cause an
  unwarranted Freeze on the Metro leg.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * GDPS Metro                                                   *
  * keywords: GDPSMETRO/K                                        *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * Improve handling of PPRCSUM events when replication legs     *
  * have duplicate SSIDs                                         *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  This PTF addresses two scenarios that can arise when the same
  SSID values are used on different replication legs. This
  configuration is not supported in GDPS, but these changes are
  intended to help identify the situation and (in one specific
  case) avoid an unwarranted Freeze.
  1. In an MGM multi-target configuration where the Metro
  secondary and GM secondary have the same SSID, when a Global
  Mirror Pause is done on the GM leg, the resulting PPRC
  suspension messages can cause GDPS to initiate an unwarranted
  Freeze on the Metro leg.
  2. If a Metro primary is in a PPRC relationship with a secondary
  LSS that has the same SSID, GDPS can not determine whether or
  not a Freeze should be done, and by design it does not perform
  one. However, GDPS does not issue a message indicating why it
  did not perform a Freeze, leaving operations staff to wonder
  why.
  

Problem conclusion

• The GDPS Metro PPRCSUM event exit routine has been changed to
  avoid initiating Freeze on Global Mirror Pause events (suspend
  code x'0F'). MTIR relationships (suspend code x'10') are also
  now ignored by the routine. Also, the routine will now provide
  additional information in GEO542I messages to assist diagnosis
  of the processing decisions made. Note, the use of duplicate
  SSID values across different replication legs remains
  unsupported, and may cause incorrect results in other scenarios.
  
  RESTART NEEDED
  It is not necessary to IPL the system to activate the fix;
  a stop and restart of the GEOXCFST task will suffice. However,
  since the GDPS SGDPLOAD library is included in the linklist,
  a F LLA,REFRESH must be performed after the fix is installed
  and prior to restarting GEOXCFST.
  

Temporary fix

Comments

APAR Information

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

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

  UI74342 UI74343

Modules/Macros

• GEOEX641
  

Fix information

• Fixed component name

  GDPS

• Fixed component ID

  694235B00

Applicable component levels

• R420 PSY UI74342

     UP21/03/10 P F103

• R430 PSY UI74343

     UP21/03/10 P F103

Fix is available

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