Define a TCP/IP connection

 

Overview

To set up TCP/IP connections basically means configuring and starting the MQ listener process. The default port for MQ listener is 1414.

There is a limit to the number of outstanding connection requests that can be queued at a single TCP/IP port. Note that this is not the same as the maximum number of clients you can attach to a local WebSphere MQ server, which is limited only by OS resources.

Server OS Max Connections
AIX 100
AT&T GIS UNIX 5
Compaq NonStop Kernel 5
Compaq OpenVMS Alpha 5
Compaq Tru64 UNIX 10
HP-UX 20
Linux 100
OS/2 Warp 10
OS/400 255
Solaris 100
SINIX and DC/OSx 5
VSE/ESA 5
Windows Server 100
Windows Workstation 100
z/OS 255

If the connection limit is reached, the client receives a return code of...

MQRC_Q_MGR_NOT_AVAILABLE
...from the MQCONN call, and an AMQ9202 error in the client error log...

mqm/errors/amqerr0n.log
Clients will retry connections, so if the volume drops, the MQCONN will eventually succeed.

To increase the number of connection requests you can make, and avoid error messages being generated by this limitation, you can have a listener listening on more than one port, or have more than one queue manager.

 

Using the Run Listener (runmqlsr) command

Use the Run Listener (runmqlsr) command to define a TCP/IP connection on a UNIX system server. For example...

runmqlsr -t tcp -m qmgr1 -p 1414
runmqlsr -t tcp -m qmgr2 -p 1415
runmqlsr -t tcp -m qmgr3 -p 1416 ...

This will start three listener processes on three different ports, connecting to three different queue managers, each listening for connection requests from MQ clients.

 

Define a TCP/IP connection on a WebSphere MQ client

You can use the KeepAlive option to make TCP/IP periodically check that the other end of the connection is still open. If it is not, the channel is closed. To use this option, create a queue manager configuration file (QM.INI) and add the following entry to it:

TCP: KeepAlive=yes

Store qm.ini file in /var/mqm

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

WebSphere is a trademark of the IBM Corporation in the United States, other countries, or both.

 

IBM is a trademark of the IBM Corporation in the United States, other countries, or both.

 

AIX is a trademark of the IBM Corporation in the United States, other countries, or both.