IC98920: WMQIPT - MQ IPT CONNECTION INTERMITTENTLY FAILS WITH MQRC_HOST_NOT_AVAILABLE ERROR.

APAR status

• Closed as program error.

Error description

• Client application intermittently fails to connect to the
  queue manager using MQIPT enabled connection. The connection
  request fails with MQRC_HOST_NOT_AVAILABLE error.
  

Local fix

• n/a
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  All users using MQIPT enabled connections.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM SUMMARY:
  The problem reported in this APAR is related to an old APAR
  IC50091. During the connection phase the MQIPT code invokes the
  gethostname API that uses the reverse DNS lookup method to
  determine the host name. This API sometimes takes a long time to
  return to the caller which causes the connection request to be
  unresponsive and might result in connection reset. This problem
  can be resolved by setting NoDNSLookups route property
  introduced in the APAR IC50091 to disable the reverse DNS lookup
  call.
  
  However, in the MQIPT code when tracing is enabled the
  gethostname method is still being invoked even if NoDNSLookups
  property is set. Hence, the connections may fail sometimes when
  tracing is enabled.
  

Problem conclusion

• The problem is fixed by verifying the NoDNSLookup property and
  based on its value invoke the correct APIs in the trace method
  that logs the host name or address in the trace files.
  

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:

Fix information

• Fixed component name

  WMQ WINDOWS V7

• Fixed component ID

  5724H7220

Applicable component levels

• R710 PSY

     UP