IJ53647: THE DISK HAS NO WWN || PR ENABLED|| "DISK FAILURE" REPORTED FOR

APAR status

• Closed as program error.

Error description

• desc-only NSD unexpectedly  reported "Disk failure" on
  its NSD server when the current FS manager was shudown
  and FS was taken over to this NSD server.
  
  PR enabled, and desc-only disks don't support PR and AIX
  logical volume is in used
  Unexpected disk down and node unhealthy, which can lead
  problem to application problems
  like for DB2.
  
  
  Reported in: 5.1.8
  

Local fix

Problem summary

• In a two-node+tiebreaker cluster using server-based cluster
  configuration when one of the nodes is powered off and the other
  node tries to run election and opens the tiebreaker disk, it
  tries to call Disk::devOpen() which has a side effect of
  retrieving the WWN from the device. This logic of retrieving WWN
  from the device and has check on disk lease before sending the
  SCSI request,hitting a deadlock there. With CCR configuraiton,
  when it goes through election and tries to access tiebreaker
  disk, it invokes OpenDevice() from CCR directly, therefore it
  doesn't hit the problem.Removing the call of wwnFromDevice()
  from Disk::devOpen() eliminates this deadlock.
  

Problem conclusion

• This problem is fixed in 5.1.9.9
  To see all Spectrum Scale APARs and their respective
  Fix solutions refer to page: 
  https://public.dhe.ibm.com/storage/spectrumscale/spectrum_scale
  _apars.html
  
  Benefits of the solution:
  Fix a deadlock situation during cluster probe in that
  configuration.
  
  Work Around:
  None
  
  Problem trigger:
  Deadlock during cluster probing (after node failure) in a two
  node cluster with tiebreaker disk and server-based cluster
  configuration
  
  Symptom:
  Deadlock during cluster probing in a two ndoe cluster with
  tiebreaker and server-based cluster configuration.
  
  Platforms affected:
  ALL Operating System environments
  
  Functional Area affected:
  Cluster configuraiton
  
  Customer Impact:
  
  High Importance
  

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

  SPEC SCALE DME

• Fixed component ID

  5737F34AP

Applicable component levels