OA44643: IST1578I HARD INOP DETECTED FOR IUTSAMEH BY ISTTSC89 CODE 002 INOP OCCURS DUE TO ECSA STORAGE SHORTAGE

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• IST1578I HARD INOP DETECTED FOR IUTSAMEH BY ISTTSC89 CODE 002
  INOP occurs due to ECSA storage shortage
  It would be better if IUTSAMEH would tolerate storage failures.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * All users of the IBM Communications Server                   *
  * for z/OS Version 2 Release 1 SNA:                            *
  * Enterprise Extender                                          *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * ECSA TI00 buffer pool growth results                         *
  * in Enterprise Extender hard INOP.                            *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Apply PTF.                                                   *
  ****************************************************************
  The problem is summarized as follows:
  
  1) Enterprise Extender is active with thousands of active
  connections.
  2) In addition to local HPR traffic, this network node
  is a main router for servicing ANR traffic for thousands
  of HPR pipes originating on application end nodes.
  3) In this case, it is speculated that there was a pause
  in TCP/IP which delayed EE packets from being delivered
  to the network.
  4) This "delay" caused TIBUF (TI00) buffers along with
  associated CSM storage to accumulate very rapidly.
  5) The available ECSA was temporarily exhausted resulting in
  an INOP occurring on the EE IUTSAMEH connections to the
  TCP/IP stack.
  
  IST1578I HARD INOP DETECTED FOR IUTSAMEH BY ISTTSC89 CODE = 0
  IST1683I HPR/IP PORT FAILURE: ID = xxxxxxxx  STATUS = 80100045
  
  6) The IUTSAMEH INOP results in an INOP for each active EE
  line.
  
  IST259I INOP RECEIVED FOR LNIP1 CODE = 02
  7) The end result, all Enterprise Extender connections are
  dropped due to the temporary storage shortage.
  
  This APAR is being taken to allow Enterprise Extender to be
  more tolerant during times of ECSA exhaustion.  Instead of
  INOPing the IUTSAMEH connection, in-flight packets will be
  simply dropped.
  

Problem conclusion

• ISTTSC89 - Has been modified to remove code which INOPs the
             IUTSAMEH interface when a storage failure occurs.
             The VRR has also been enhanced to allow up to
             five abends in a given 5-minute interval before
             INOPing the IUTSAMEH connection.  Prior to this
             change, only a single abend would cause the
             IUTSAMEH interface to INOP.
  
  INOPCODE  - Removed INOP reasons 1, 2 and 3 for module
              ISTTSC89.  INOP reason 4 still remains for
              the repetitive abend case described above.
  ISTTSCIC  - Recompile Only
  ISTMPNCB  - Added various PD variables to count and
              record the TOD clock of the packet discards.
              Variables associated with the VRR recovery
              are also defined here as well. The additional
              PD variables required the MPNCB to be
              increased in size.
  ISTAUCLA - Included for maintenance purposes.
  Modules recompiled for MPNCB size increase:
  ISTLLCFT  ISTRAFDC  ISTTSCAM  ISTTSZCT
  ISTINCTS  ISTTSCMS  ISTTSCDP  ISTTSC8E
  ISTTSC86  ISTTSC87  ISTTSC88  ISTTSC8S
  ISTTSCND
  

Temporary fix

• *********
  * HIPER *
  *********
  

Comments

APAR Information

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

  OA44450

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

  UA72669

Modules/Macros

• ISTTSCMS ISTTSZCT ISTTSCAM ISTTSCDP ISTLLCFT ISTTSC8E ISTRAFDC
  ISTTSCND ISTINCTS ISTTSCIC ISTTSC8S ISTTSC86 ISTTSC87 ISTTSC88
  ISTAUCLA ISTTSC89
  

Fix information

• Fixed component name

  VTAM V4 MVS/ESA

• Fixed component ID

  569511701

Applicable component levels

• R210 PSY UA72669

     UP14/04/29 P F404

Fix is available

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