Noryungi's Journal: So... Can't restart MQSeries, hmmmm?

It's a tragedy to work with useless software such as this deep fried piece of ..... named MQSeries, for verily, I tell thee, rarely have I seen such a useless piece of spaghetti application.

OK, enough ranting, here is the nitty-gritty of it:

If you get MQSeries messages -- on a Red Hat Linux platform -- such as:

06/02/2008 09:11:58 PM - Process(10406.238) User(mqm) Program(amqrmppa)
AMQ6184: An internal WebSphere MQ error has occurred on queue manager Wolfenstein.
 
EXPLANATION:
An error has been detected, and the WebSphere MQ error recording routine has
been called. The failing process is process 10406.
ACTION:
Use the standard facilities supplied with your system to record the problem
identifier, and to save the generated output files. Contact your IBM support
center. Do not discard these files until the problem has been resolved.

Or a bit like this:

06/03/2008 09:20:10 AM - Process(4092.20) User(mqm) Program(runmqlsr)
AMQ9999: Channel program ended abnormally.
 
EXPLANATION:
Channel program 'JAVA.CHANNEL' ended abnormally.
ACTION:
Look at previous error messages for channel program 'JAVA.CHANNEL' in the error
files to determine the cause of the failure.

HINT#1: check the files named /var/mqm/errors and /var/mqm/qmgrs/wolfenstein/errors, for instance... (replace 'wolfenstein' by the name of your queue, of course).

HINT#2: if you only see two mqm processes when you type ps faxu | grep -i mqm, something is wrong...

Well, my friend, your MQSeries just crashed and crapped all over itself. Information about this is sparse on the Internet, but Google is your friend and should be able to give you more links than you can shake a stick at.

Fortunately, getting MQSeries unstuck is not too difficult, just follow the four easy steps below... All of these steps should be performed as root:

1. Check that all 'mqm' processes are stopped with ps faxu | grep -i mqm | grep -v grep, if there are processes left, kill them all with pkill -9 -u mqm.
2. Delete all sockets left in /tmp with: rm -v /tmp/MQ*, but watch out, as there may be a very large number of them...
3. Clean up all temporary files and whatnot with the command: su - mqm -c "/opt/mqm/bin/amqiclen -x -m QMGR" (return code should be zero).
4. Finally, clean up all used IPCS resources with the commands ipcs -a and ipcrm (do a man ipcrm for more information).

That's it! MQM should now be able to restart without any problem. Ain't that helpful?