IJ04486: FUSER RUN ON A LOCAL FILESYSTEM CAN HANG DUE TO NFS DOWN

APAR status

• Closed as program error.

Error description

• In certain PowerHA environments fuser run on a local
  filesytem has been seen to hang due to the NFS network
  down. It would seem a defect that fuser run on a local
  filesytem would be affected by a problem with NFS.
  The current design of fuser depends on accessing all
  processes one at a time to determine if any of their
  files belong to the local file system. Currently a
  stat call is used to determine the attributes of the
  precesse's executable. If the executable is NFS
  mounted the stat depends on NFS network being up to
  be successful and can hang if it is not up.
  What is needed is a new stat call that can obtain
  the attributes known locally which do not need to be
  accessed over the network.
  

Local fix

• Using soft NFS mounts that would return an error instead
  hanging can be used as workaround.
  

Problem summary

• fuser command hangs when NFS is down, even when not run on an
  NFS file/filesystem
  

Problem conclusion

• We now ignore NFS processes that we know will not be a match
  when fuser is run on a local file/ filesystem
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

  IJ03793

• APAR is sysrouted TO one or more of the following:

  U883844

Fix information

• Fixed component name

  AIX V7.1

• Fixed component ID

  5765H4000

Applicable component levels

• R710 PSY U883844

     UP19/01/29 I 1000