Changing IBM MQ configuration information in .ini files on Multiplatforms

You can change the behavior of IBM® MQ or an individual queue manager to suit the needs of your installation by editing the information in the configuration (.ini) files. You can also change configuration options for IBM MQ MQI clients.

About this task

You can change IBM MQ configuration information at the level of the node or the queue manager by changing the values that are specified on a set of configuration attributes (or parameters) that govern IBM MQ.

A configuration file (or 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, such as log functions, channel functions, and installable services. You can modify IBM MQ configuration attributes within the following configuration files:

IBM MQ configuration file, mqs.ini: The mqs.ini file effects changes on the node as a whole. There is one mqs.ini file for each IBM MQ installation.; Because the IBM MQ configuration file is used to locate the data associated with queue managers, a nonexistent or incorrect configuration file can cause some or all MQSC commands to fail. Also, applications cannot connect to a queue manager that is not defined in the IBM MQ configuration file.
Installation configuration file, mqinst.ini: On AIX® and Linux® systems, the installation configuration file, mqinst.ini, contains information about all the IBM MQ installations. The mqinst.ini file must not be edited or referenced directly since its format is not fixed, and could change. Instead, you must edit it using commands.
Queue manager configuration file, qm.ini: The qm.ini file effects changes for specific queue managers. There is one qm.ini file for each queue manager on the node.
IBM MQ MQI client configuration file, mqclient.ini: Configuration options for IBM MQ MQI clients are held separately, in the client configuration file, which is generally named mqclient.ini.
Activity trace configuration file, mqat.ini: The mqat.ini file is used to configure activity trace behavior.

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

You lose a configuration file. (Recover it from backup if you can.)
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 IBM Support.

Important: Any changes that you make to a configuration file usually do not take effect until the next time the queue manager is started.

Points to note about editing configuration files:

The values of the attributes of a configuration file are set according to the following priorities:
- Parameters that are entered on the command line take precedence over values that are defined in the configuration files.
- Values that are defined in the qm.ini files take precedence over values that are defined in the mqs.ini file.
After installation, you can edit the default values in the IBM MQ configuration files.
When backing up a queue manager, remember to include both its configuration file (qm.ini) and the central IBM MQ configuration file (mqs.ini).
If you set an incorrect value on a configuration file attribute, the effect is the same as missing out the attribute entirely. The value is ignored and an operator message is issued to indicate the problem.
On IBM i, the .ini files are stream files resident in the IFS.
There are a number of syntax rules for the format of the mqat.ini file. For more information, see Application activity trace Configuring activity trace behavior using mqat.ini.

Procedure

Before you edit a configuration file, back it up so that you have a copy that you can revert to, if the need arises.
Edit the .ini configuration file in one of the following ways:
- Manually by using a standard text editor. Comments can be included in configuration files by adding a ; or a # character before the comment text. If you want to use a ; or a # character without it representing a comment, you can prefix the character with a \ character. The character is then used as part of the configuration data.
- Automatically, by using commands that change the configuration of queue managers on the node. For more information, see Commands reference.
  For example, the Windows specific command amqmdain will update a subset of the qm.ini properties automatically. For more information, see amqmdain.
- On Linux (x86 and x86-64) and Windows, you can update a subset of the qm.ini properties by using IBM MQ Explorer. For more information, see Configuring IBM MQ using MQ Explorer.
  Note: Because there are significant implications to changing installable services and their components, the installable services are read-only in the IBM MQ Explorer. Therefore, you must make any changes to installable services by editing the qm.ini file. For more information, see Service stanza of the qm.ini file.