IT15737: IBM MQ APPLIANCE INTERMITTENTLY REBOOTS WITH NO ERRORS REPORTED

APAR status

• Closed as program error.

Error description

• Some users deploying an MQ Appliance have reported
  intermittent reboots of a running appliance.
  No errors are reported in the system logs when the appliance
  restarts.
  Queue managers on the affected appliance that are part of an HA
  pair
  fail over to the standby instance as expected during the
  shutdown phase of the reboot.
  

Local fix

• The watchdog timer can be disabled by running a remote ipmitool
  request to the affected appliance@
  
  ipmitool -L operator -I lanplus -H <ipmi-channel-IP> -U
  <ipmi_user> -P <ipmi_password> mc watchdog off
  
  
  When run successfully, the command output will report:
  Watchdog Timer Shutoff successful -- timer stopped
  
  
  Please note that if the watchdog timer is disabled, then the IBM
  MQ Appliance firmware may falsely report an intrusion detection
  warning if the connection is lost between the low-level firmware
  and the rest of the system.
  
  
  
  The watchdog timer can be re-enabled by running the following
  remote command:
  
  ipmitool -L operator -I lanplus -H <ipmi-channel-IP> -U
  <ipmi_user> -P <ipmi_password> mc reset warm
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users of the IBM MQ Appliance
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  The IBM MQ Appliance low-level firmware makes use of a "watchdog
  timer" to monitor the state of the system, and restart the
  appliance if an unrecoverable system state is detected.
  
  An error in the low level firmware meant that it was possible
  for the low-level firmware's watchdog timer to lose
  communication with the rest of the system, and incorrectly
  determine that the system had entered an unrecoverable state,
  triggering a reboot of the appliance.
  

Problem conclusion

• The low-level firmware within the MQ appliance has been updated
  to prevent this loss of communication, in order to maintain
  normal operation of the watchdog timer.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v8.0       8.0.0.5
  
  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

  IBM MQ APPL M20

• Fixed component ID

  5725S1400

Applicable component levels

• R800 PSY

     UP