Changes for active logs

You can add to, delete from, and record entries in the BSDS for active logs using the change log utility. Examples only are shown here; replace the data set names shown with the ones you want to use. For more details of the utility, see The change log inventory utility (CSQJU003).

Adding record entries to the BSDS

If an active log has been flagged as "stopped", it is not reused for logging; however, it continues to be used for reading. Use the access method services to define new active log data sets, then use the change log inventory utility to register the new data sets in the BSDS. For example, use:

NEWLOG DSNAME=MQM111.LOGCOPY1.DS10,COPY1
NEWLOG DSNAME=MQM111.LOGCOPY2.DS10,COPY2

If you are copying the contents of an old active log data set to the new one, you can also give the RBA range and the starting and ending time stamps on the NEWLOG function.

Deleting information about the active log data set from the BSDS

To delete information about an active log data set from the BSDS, you could use:

DELETE DSNAME=MQM111.LOGCOPY1.DS99
DELETE DSNAME=MQM111.LOGCOPY2.DS99

Recording information about the log data set in the BSDS

To record information about an existing active log data set in the BSDS, use:

NEWLOG DSNAME=MQM111.LOGCOPY1.DS10,COPY2,STARTIME=19930212205198,
              ENDTIME=19930412205200,STARTRBA=6400,ENDRBA=94FF

You might need to insert a record containing this type of information in the BSDS because:

Enlarging the active log

This procedure must only be used when the queue manager is inactive:

  1. Stop the queue manager. This step is required because WebSphere MQ allocates all active log data sets for its exclusive use when it is active.
  2. Use Access Method Services ALTER with the NEWNAME option to rename your active log data sets.
  3. Use Access Method Services DEFINE to define larger active log data sets.

    By reusing the old data set names, you do not have to run the change log inventory utility to establish new names in the BSDSs. The old data set names and the correct RBA ranges are already in the BSDSs.

  4. Use Access Method Services REPRO to copy the old (renamed) data sets into their respective new data sets.
  5. Start the queue manager.

If all your log data sets are the same size, your system will be operationally more consistent and efficient. If the log data sets are not the same size, it is more difficult to track your system's logs, and so space can be wasted.