IZ71073: SCRIPT WITH PIPES LEAVES TR RUNNING WHEN RUN AS A TASK

Tivoli Framework Patch 4.3.1-LCF-0016
Tivoli Framework Patch 4.3.1-LCF-0010

APAR status

• Closed as program error.

Error description

• Environment: UNIX based endpoints running version 411xx lcfd
  Description: submitting a task of a script such as:
  ----------------------
  #!/bin/sh
  echo "Begin:"
  MYPASS=`< /dev/urandom  tr -dc A-Za-z0-9 | head -c8`
  echo $MYPASS
  echo "End."
  ----------------------
  to run on a UNIX endpoint will run and exit with return code 0
  but leave 'tr' running and consuming CPU after posting a
  "tr: write error: Broken pipe" error message.
  

Local fix

• Don't pipe through tr or awk in a task
  

Problem summary

• * Users Affected:
  Use TMF4.1.1 or 4.3.1 to run the tasks which contain pipe.
  
  * Problem Description:
  If the task that endpoint executes contains some pipes, the
  commands in pipe may reports "broken pipe"/"write error"
  exception(signal) when writing the pipe when other command
  closes the other end of the pipe ahead of expectation (as
  design). In fact the task executes successfully as expected. But
  such signal (broken pipe) will be reported up to TMR/ManagedNode
  as task error output, misleading user to regard the task as
  failed. And in some particular cases, the command that writing
  the pipe, such as "tr", may hang on and consume much CPU time
  after task is done.
  
  * Recommendation:
  Apply fix pack 4.3.1-LCF-0010 when available (around 2010 June).
  Apply fix pack 4.1.1-LCF-xxxx (TBD) available after 2010
  June.
  

Problem conclusion

• The fix modifies the response type of signal SIGPIPE ("broken
  pipe"), from "ignored" to "default", on the child process
  of lcfd, such as task process. This avoid the signal SIGPIPE is
  put up to TMR/ManagedNode as exception in the task output.
  
  The fix for this APAR is contained in the following maintenance
  packages:
  
  | Fix pack | 4.3.1-LCF-0010  (when available around 2010 June)
  | Fix pack | 4.1.1-LCF-xxxx  (TBD, available after 2010
  June)
  

Temporary fix

• Temporary Fix was sent to customer on Mar.8 for test on AIX, and
  this fix is built on 4.1.1-TMF-0104 + 4.1.1-LCF-0055, so
  customer should upgrade to this patch level first before
  testing.
  

Comments

• Since customer has tested the temp fix in his/her test env
  without problem, I want to close this APAR.
  The APAR fix will be built into next GA fix pack, 4.1.1 and
  4.3.1.
  The next 4.3.1 GA patch is expected to be available around 2010
  June, or later.
  

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

  MGMT. FRAMEWORK

• Fixed component ID

  5698FRA00

Applicable component levels

• R411 PSY

     UP

• R431 PSY

     UP