IBM MQ configuration files for IBM i

Use this information to understand the methods for configuring IBM MQ for IBM i.

On IBM i, you modify IBM MQ configuration attributes within:

  • An IBM MQ configuration file, mqs.ini, effect changes on the node as a whole. There is one mqs.ini file for each IBM MQ installation.
  • A queue manager configuration file, qm.ini, effect changes for specific queue managers. There is one qm.ini file for each queue manager on the node.
Note that .ini files are stream files resident in the IFS.

A configuration file (which can be referred to as a stanza file) contains one or more stanzas, which are groups of lines in the .ini file that together have a common function or define part of a system, for example, log functions and channel functions. Any changes made to a configuration file do not take effect until the next time the queue manager is started.


Editing configuration files

Before editing a configuration file, back it up so that we have a copy we can revert to if the need arises.

We can edit configuration files either:

  • Automatically, using commands that change the configuration of queue managers on the node.
  • Manually, using the EDTF CL editor.

We can edit the default values in the IBM MQ configuration files after installation. If you set an incorrect value on a configuration file attribute, the value is ignored and an operator message is issued to indicate the problem. (The effect is the same as missing out the attribute entirely.)

When you create a new queue manager:

  • Back up the IBM MQ configuration file.
  • Back up the new queue manager configuration file.


When do you need to edit a configuration file?

You might need to edit a configuration file if, for example:

  • You lose a configuration file; recover from backup if possible.
  • You need to move one or more queue managers to a new directory.
  • You need to change your default queue manager; this could happen if you accidentally delete the existing queue manager.
  • You are advised to do so by your IBM Support Center.


Configuration file priorities

The attribute values of a configuration file are set according to the following priorities:

  • Parameters entered on the command line take precedence over values defined in the configuration files.
  • Values defined in the qm.ini files take precedence over values defined in the mqs.ini file.


The IBM MQ configuration file mqs.ini

The IBM MQ configuration file, mqs.ini, contains information relevant to all the queue managers on an IBM MQ installation. It is created automatically during installation. In particular, the mqs.ini file is used to locate the data associated with each queue manager.

The mqs.ini file is stored in /QIBM/UserData/mqm

The mqs.ini file contains:

  • The names of the queue managers.
  • The name of the default queue manager.
  • The location of the files associated with each queue manager.
  • Information identifying any API exits (see Configure API exits for more information).


Queue manager configuration files, qm.ini

A queue manager configuration file, qm.ini, contains information relevant to a specific queue manager. There is one queue manager configuration file for each queue manager. The qm.ini file is automatically created when the queue manager with which it is associated is created.

A qm.ini file is held in the mqmdata directory/QMNAME/qm.ini, where mqmdata directory is /QIBM/UserData/mqm by default and QMNAME is the name of the queue manager to which the initialization file applies.

Note:
  1. We can change the mqmdata directory in the mqs.ini file.
  2. The queue manager name can be up to 48 characters in length. However, this does not guarantee that the name is valid or unique. Therefore, a directory name is generated based on the queue manager name. This process is known as name transformation. See Understanding IBM MQ for IBM i queue manager library names for further information.