IT22419: All username/password authentication requests hang. Queue manager is configured to request via PAM

APAR status

• Closed as program error.

Error description

• A queue manager is configured (via an AUTHINFO object) to use
  PAM to provide username/password authentication.
  
  After an error in processing one of these, all subsequent
  requests hang.
  
  At least one FDC record is generated with the following details:
  
  Probe Id          :- XC514090
  Component         :- xlsRWMutexRequest
  Major Errorcode   :- xecL_W_LONG_LOCK_WAIT
  Probe Description :- AMQ6150: WebSphere MQ semaphore is busy.
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users who have configured the queue manager to request
  username/password authentication using PAM, who suffer a failure
  within that mechanism (the root cause for that failure is
  outside the scope and control of the MQ product).
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  The process that is started to check the username/password using
  PAM is amqoampx.
  
  On one system we saw that:
  - this process could fail to write output back to the process
  that started it
  - the parent process would not be returned from its read() call,
  even though the process was ended.
  
  The queue manager holds a mutex while this activity takes place,
  to prevent changes to the AUTHINFO configuration from affecting
  currently-running PAM auth requests.
  
  This mutex is never released because of the failures mentioned
  above, and as a result, the queue manager ceases to be able to
  offer authentication to newly connecting applications.
  

Problem conclusion

• The MQ code has been changed to use a more robust mechanism for
  waiting and reading the output from amqoampx into the process
  that starts it.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v8.0       8.0.0.8
  v9.0 CD    9.0.5
  v9.0 LTS   9.0.0.3
  
  The latest available maintenance can be obtained from
  'WebSphere MQ Recommended Fixes'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037
  
  If the maintenance level is not yet available information on
  its planned availability can be found in 'WebSphere MQ
  Planned Maintenance Release Dates'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309
  ---------------------------------------------------------------
  

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 BASE MULTIP

• Fixed component ID

  5724H7251

Applicable component levels

• R800 PSY

     UP