+

Search Tips | Advanced Search

MQCHLLIB

MQCHLLIB specifies the directory path to the file containing the client channel definition table (CCDT). The file is created on the server, but can be copied across to the IBM MQ MQI client workstation.

If MQCHLLIB is not set, the path for the client defaults to:

For the crtmqm and strmqm commands, the path defaults to one of two sets of paths. If datapath is set, the path defaults to one of the first set. If datapath is not set, the path defaults to one of the second set.

Or:

where:

Notes:
  1. If you are using IBM MQ for z/OSĀ® as your server, the file must be kept on the IBM MQ client workstation.
  2. If set, MQCHLLIB overrides the path used to locate the CCDT.
  3. MQCHLLIB can contain a URL which works in combination with the MQCHLTAB environment variable (see Web addressable access to the client channel definition table).
  4. Environment variables, such as MQCHLLIB, can be scoped to a process, or a job, or system-wide, in a platform-specific way.
  5. If you set MQCHLLIB system-wide on a server, it sets the same path to the CCDT file for all the queue managers on the server. If we do not set the MQCHLLIB environment variable, the path is different for each queue manager. Queue managers read the value of MQCHLLIB, if it is set, on either the crtmqm or strmqm command.
  6. If you create multiple queue managers on one server, the distinction is important, for the following reason. If you set MQCHLLIB system-wide, each queue manager updates the same CCDT file. The file contains the client-connection definitions from all the queue managers on the server. If the same definition exists on multiple queue managers, SYSTEM.DEF.CLNTCONN for example, the file contains the latest definition. When you create a queue manager, if MQCHLLIB is set, SYSTEM.DEF.CLNTCONN is updated in the CCDT. The update overwrites the SYSTEM.DEF.CLNTCONN created by a different queue manager. If you modified the earlier definition, your modifications are lost. For this reason, you must consider finding alternatives to setting MQCHLLIB as a system-wide environment variable on the server.
  7. The MQSC and PCF NOREPLACE option on a client-connection definition does not check the contents of the CCDT file. A client-connection channel definition of the same name that was previously created, but not by this queue manager, is replaced, regardless of the NOREPLACE option. If the definition was previously created by the same queue manager, the definition is not replaced.
  8. The command, rcrmqobj -t clchltab deletes and re-creates the CCDT file. The file is re-created with only the client-connection definitions created on the queue manager that the command is running against.
  9. Other commands that update the CCDT modify only the client-connection channels that have the same channel name. Other client-connection channels in the file are not altered.
  10. The path for MQCHLLIB does not need quotations marks.


Examples

To set this variable use one of these commands: