IJ40064: HANG DEADLOCK DURING NETWORK INSTABILITY

APAR status

• Closed as program error.

Error description

• Network instability triggering socket reconnects
  can cause certain Spectrum Scale messages
  to be lost and not re-transmitted.
  Additionally, its network instability provokes
  a node failure, these lost messages can prevent
  the cluster from moving forward with the
  cluster-wide node leave protocol.
  This hang can prevent loss of cluster
  function including file system availability.
  

Local fix

• Restart the cluster.
  

Problem summary

• Network instability triggering socket reconnects
  can cause certain Spectrum Scale messages
  to be lost and not re-transmitted.
  Additionally, its network instability provokes
  a node failure, these lost messages can prevent
  the cluster from moving forward with the
  cluster-wide node leave protocol.
  This hang can prevent loss of cluster
  function including file system availability.
  

Problem conclusion

• This problem is fixed in 5.1.2 PTF 5
  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:
  No more deadlock
  
  Work Around: Restart the cluster.
  Problem trigger:  Node expel during socket reconnects.
  Symptom: Hang/Deadlock/Unresponsiveness/Long Waiters
  Platforms affected:  Linux Only
  Functional Area affected: ESS/GNR
  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 STD

• Fixed component ID

  5737F33AP

Applicable component levels