Userdata directory

We can use the userdata directory to store persistent application status.

Each IBM MQ queue manager has a dedicated filesystem for its persistent state, which includes both its queue data and recovery log. The filesystem includes a userdata directory used to store persistent status information for the applications. See Directory content on Unix and Linux Systems and Directory content on Windows systems.

• In RDQM configurations so that application information also moves when a queue manager fails over to another node (see Storing persistent application status).
• For multi-instance queue managers so their application state is located with their queue manager data on the shared network filesystem.
• More generally, where applications are configured queue manager services.

If you choose to store application state in the userdata directory, we must be aware that data written to this location might consume the available disk space allocated to the queue manager. We must ensure that sufficient disk space remains available for the queue manager to write queue data, logs, and other persistent state information.

The userdata directory has mqm user and group ownership, and it is world readable so users can access it without needing to be in the IBM MQ administrator group (that is, mqm). We cannot modify the permissions of the userdata directory, but we can create content in it with whatever ownership and permissions you require.