Once again, changes made to the Agent Configuration (.cab) file are not effective until they are applied. For example, lets imagine that the new IMS Segments will be rolled out next weekend:
In our example, no changes were required to the Capture Agent configuration. If changes had been necessary, they would be made after the Log Reader Capture was stopped using one or more sqdconf Job steps.
Changes to the Publisher Agent configuration were required. If those changes were effective immediately or automatically at the next start, then these changes could not be performed until the production capture is stopped for the migration during the week-end. Otherwise, the risk exists that the capture agent may go down for unrelated production issues, and the new change would be activated prematurely.
Forcing a distinct and explicit apply step, insures that such changes can be planned and prepared in advance, without putting the current production replication in jeopardy. This allows publisher agent maintenance to be done outside of the critical upgrade path.
//*----------------------------------------
//*- STOP THE AGENT
//*----------------------------------------
//STOP EXEC SQDCONF,OWNER=&SYSUID
//SQDPARMS DD *
stop /home/sqdata/imspub1/IMSPUB1.cab
//*
//*----------------------------------------
//*- APPLY UPDATED CONFIGURATION FILE
//*----------------------------------------
//APPLY EXEC SQDCONF,OWNER=&SYSUID
//SQDPARMS DD *
apply /home/sqdata/imspub1/IMSPUB1.cab
//*
//*----------------------------------------
//*- START THE AGENT
//*----------------------------------------
//START EXEC SQDCONF,OWNER=&SYSUID
//SQDPARMS DD *
start /home/sqdata/imspub1/IMSPUB1.cab
//* Console commands that may be issued, with the proper authority include:
| Command Function | Description |
|---|---|
| P <task_name> | Stops and unmounts the agent immediately |
| F <task_name>,PAUSE | Pauses the agent |
| F <task_name>,RESUME | Resumes the agent after a pause |
| F <task_name>,DISPLAY | Display of the agent cab file with the output being written to SYSPRINT in the running STC |
| F <task_name>,STOP | Stops the agent but leaves it mounted |
| F <task_name>,STOP,UNMOUNT | Stops and unmounts the agent (same as P command) |
| F <task_name>,STOP,FLUSH | Stops the agent after flushing out any UOWs that began before the command was issued, then unmounts |
| F <task_name>,STOP,FLUSH,FAILOVER | Same as STOP,FLUSH except that it instructs downstream engines to try to reconnect for up to 10 minutes |
| F <task_name>,START | Starts an agent that was previously stopped, but still mounted |
| F <task_name>,APPLY | Applies pending cab file changes to the agent's cab file. Agent must be mounted, stopped in order to apply |