IV03789: SNADAEMON PROCESS HANGS WHEN 'SNA STOP' COMMAND ISSUED

Communications Server for AIX, Version 6.3 -- Last PTFs

APAR status

• Closed as program error.

Error description

• When stopping SNA using the commands "sna stop" or
  "service snastart stop", the process "snadaemon" hangs
  and does not terminate.
  

Local fix

• reboot
  

Problem summary

• USERS AFFECTED: All users.
  
  PROBLEM DESCRIPTION:
  When stopping SNA, the snadaemon process hangs and does
  not terminate.
  
  PROBLEM SUMMARY:
  The snadaemon process hangs on the catclose system call,
  which calls munmap(), which is waiting on response to a
  semaphore from snadaemon. An attempt was made to fix this
  with APAR LI73947, but that fix was insufficient; the
  problem was just shifted into the exit() code which will
  still attempt to close the catalog. An internal trace
  captured shows that this close attempt interfered with
  another module closing file handles to Streams.
  

Problem conclusion

• It is possible for there to be a locking race if the
  termination signal to the daemon arrives while the
  catalog is being used in the main context of the daemon.
  For APAR LI73947, the code was modified to not close
  the catalog from the signal catcher. The code has now
  been modified so the termination code does not run
  inside the signal handler at all, so the close of the
  catalog does not clash with closing Streams. This
  corrects LI73947.
  

Temporary fix

• snadaemon
  

Comments

APAR Information

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

  LI75519

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

Fix information

• Fixed component name

  CS AIX V6.X

• Fixed component ID

  5765E5100

Applicable component levels

• R631 PSY U848721

     11/11/18 I 1000