PH62206: BETWEEN 1 AM AND 1:05 AM (UTC), AN ACCELERATOR ON IBM Z WITH MAINTENANCE LEVEL 7.5.12.X SUDDENLY GOES DOWN

APAR status

• Closed as documentation error.

Error description

• Customers running Accelerator maintenance level 7.5.12.x on IBM
  Z can be facing the following issue:
  Between 1 am and 1.05 am (UTC), the accelerator out of the
  sudden goes down. An attempt to connect to the accelerator for
  creation of a trace ends with
  
  - SQLCODE is 466, SQLSTATE 0100C and
  - message "AQT10503E An accelerator or Db2 Data Gate instance
  could not be contacted".
  
  Diagnostic information with details about the connectivity
  problem: DRDATCPIPException: Connecting to the remote host
  failed on message type 0x0000: The connection was refused.
  
  No one is listening on the remote address.
  Error code (1128).
  
  The issue can be accompanied by the following information
  in DB2MSTR:
  DSNLIENO TCP/IP CONVERSATION FAILED 839
  DSNX870I -DDD3 DSNX8EKG ACCELERATOR DZZADB2D IS NOT ONLINE
  If Integrated Synchronization is used, the following message
  
  is seen as well:
  DSNI092I -DDD3 DSNILGRT -TIMEOUT CAUSED TERMINATION OF
  ASYNCHRONOUS LOG READER TASK FOR SESSION ID ...
  
  A DISPLAY ACCEL REPORT results in
  DSNX830I -DDD2 DSNX8CDA ACCELERATOR MEMB STATUS REQUESTS ACTV
  ... LOCATION=DZZADB2D FLATLINE
  DISPLAY ACCEL REPORT COMPLETE
  
  When accessing the Admin UI, the appliance runtime, appliance
  authentication service, appliance data service, and db2
  accelerator show status "red".
  
  In Data Studio, the Replication start/stop button is not
  visible.
  
  Using a Reset w/o wipe brings the accelerator back again.
  
  A fix for this issue will be delivered with Accelerator
  maintenance level 7.5.13.
  
  Additional keywords:
  TS016548927 TS016593832 TS015286153 TS016604206 TS016794016
  GH/.../Everest/Customer-Cases/issues/720 sytemctl restart
  docker DT391431
  AQT10503E DSNX870I DSNX830I FLATLINE
  

Local fix

• Using a Reset w/o wipe brings the accelerator back again.
  

Problem summary

• Problem Summary:
  The accelerator suddenly faces an outage starting at 01:01 AM
  UTC. For more details see the APAR Error description.
  
  
  Users Affected:
  Users of Db2 Analytics Accelerator for z/OS V7.5, maintenance
  level 7.5.12.x.
  
  
  Problem Scenario:
  Due to a race condition, the accelerator suddenly goes down at
  01:01 AM UTC.
  
  
  Problem Symptoms:
  Starting at 01:01 AM UTC, the accelerator no longer reacts on
  any network activity. For a final proof that an outage with
  similar symptoms goes back to the issue described in this APAR,
  an SSC dump is required.
  

Problem conclusion

• The issue has been completely fixed with Accelerator maintenance
  level 7.5.13.
  Upgrade your Accelerator environment(s) accordingly.
  

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

Applicable component levels