PI06947: The Gateway daemon throws a ConcurrentModificationException when an IPIC connection fails to connect

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• The following message is written to the CICS TG log and
  requests are not sent to the CICS server:
  CTG8433E Connection failure for IPIC connection to CICS server
  <CICS_server_name> reason = java.io.IOException: Already
  connected.
  
  A ConcurrentModificationException is reported: Exception in
  thread "Receiver-<URL>:<Port>(n)"
  java.util.ConcurrentModificationException at
  java.util.Vector$Itr.checkForComodification(Vector.java:1167) at
  java.util.Vector$Itr.next(Vector.java:1144) at
  com.ibm.ctg.server.isc.SessionPool.close(Unknown Source) at
  com.ibm.ctg.server.isc.Connection.closeSocket(Unknown Source)
  at com.ibm.ctg.server.isc.Connection.close(Unknown Source) at
  com.ibm.ctg.server.isc.Connection.connectionError(Unknown Source
  at com.ibm.ctg.server.isc.Receiver.run(Unknown Source) at
  java.lang.Thread.run(Thread.java:780)
  
  Additional search words msgCTG8433E msgCTG8433 CTG8433
  

Local fix

• No work-around, the Gateway daemon must be restarted
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of IPIC-connected CICS servers     *
  ****************************************************************
  * PROBLEM DESCRIPTION: The Gateway daemon throws a             *
  *                      ConcurrentModificationException when an *
  *                      IPIC connection fails to connect        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  When an IPIC connection can not be established, the sessions for
  the IPIC connection are terminated. The Gateway daemon throws a
  ConcurrentModificationException if the session termination
  occurs before the session initialization has completed. The
  Gateway daemon does not terminate. Further attempts to connect
  to the CICS server fail.
  

Problem conclusion

• CICS TG has been corrected and will not throw the reported
  ConcurrentModificationException when a connection attempt fails.
  

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:

  PI13189 UI15986

Modules/Macros

• CTG00201 CTG00204
  

Fix information

• Fixed component name

  CTG V9 FOR Z/OS

• Fixed component ID

  5655Y2000

Applicable component levels

• R900 PSY UI15986

     UP14/03/20 P F403

Fix is available

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