OW28883: CP-CP SESSIONS NOT ESTABLISHED

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• conwinner cpsvcmg bind not sent due to TPT_INSTANCE_LIMIT of
  30 is reached. More than 30 pending GBINDs for other CPs are
  queued.  Status may show PSEST.
  

Local fix

• ZAP in ISTXPCVT available to increase the limit
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All using APPN.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION:   CP to CP session activation hangs.    *
  *                      The ConLoser session came active, but   *
  *                      the ConWinner session was not driven.   *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
    The CONWINNER portion of a CP-CP session was not being
  activated after an INOP condition.  Inactivating and activating
  a link again would cause the CONLOSER session to come active
  again, but the CONWINNER would remain inactive.
    Analysis of the CONLOSER activation showed a BIND came in and
  got a +RSP, followed by an ATTACH(CP Capabilities) coming in.
  This was queued to the CP Capabilities TP (id 22F0F0F1 in the
  table based on ATCXPCRT), but was not processed because
  TPT_INSTANCE_COUNT was equal to the TPT_INSTANCE_LIMIT of 30 for
  this transaction program.
    This TP had been driven 30 prior times and had sent a
  CP_CP_SESSION_ACT (CSA) to the SSC component of VTAM and these
  30 TP instances were waiting for replies.  Timing during the
  INOP processing had caused SSC to PARK these CSA's on 30 ANDCBs
  waiting for the CONWINNER sessions to become active.
    The trace had wrapped, so the flow leading up the CSA's
  being PARKed is missing, but AND_CW_TP_SIGNAL_EXPECTED was on
  in the 30 ANDCBs with the parked CSAs.  SSC had sent a START_TP
  for the Request_CP_Capabilities_TP and had not gotten a reply.
  This TP was also at its instance limit of 30.  For the 30
  instances of this TP, there were SIBs for the ConWinner sessions
  in a PSESST status.  The BIND had been sent but had not been
  responded to because the VR to the NCP was blocked.
  

Problem conclusion

• ISTXPCVT has been changed to have the TPT_INSTANCE_LIMIT
  removed for the Request CP Capablities TP and the CP
  Capabilities TP.  This will prevent CP to CP session activation
  from being limited when normal LU to LU session activation is
  not limited.  This should allow additional CP to CP sessions to
  come active when a limited number are hung for some reason.
  

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:

  OW32452 VM61854 DY44918

Modules/Macros

• ISTXPCVT
  

Fix information

• Fixed component name

  VTAM V4 MVS/ESA

• Fixed component ID

  569511701

Applicable component levels

• R201 PSY UW43278

     UP97/12/02 P F712

• R301 PSY UW43279

     UP97/12/02 P F712

• R401 PSY UW43280

     UP97/12/02 P F712

Fix is available

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