I am looking for a command to change the message broker message flow instance in the run time. I know it is quite easy with MB explorer. But I am more interested towards the server side mqsi command. Ours is a AIX env with message broker 8 installed.
The number of instances a message flow has on the execution group is configured in the BAR file, before deployment. If you want to change the number of additional instances you will need to redeploy your flow.
You can use the mqsiapplybaroverride command to change the configuration of the flow in the BAR file, and the mqsideploy command to redeploy the BAR.