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Offloading Disk Journal Files

What Happens When You Offload a Disk Journal File

The ARCHIVE JOURNAL utility statement offloads the contents of a disk journal file to an archive journal file. It also rebuilds the disk journal file, condensing all before images for each active transaction into new journal blocks at the beginning of the file. This process creates a journal file that contains only those before images that are needed if an active transaction aborts or requests rollback.

Creating Multiple Archive Files

CA IDMS/DB will offload the disk journal files to multiple archive files if more than one is defined in the DMCL used when executing the ARCHIVE JOURNAL utility statement. By creating multiple archive files, you increase the likelihood that a readable archive file is available in the event it is needed for manual recovery. If an I/O error is encountered while writing to one of the archive files, a warning message is issued and offloading continues without further writes to the damaged file. If all archive files incur write errors, execution is aborted.

When to Offload

You normally offload disk journal files only when:

The procedure for each scenario is provided next followed by a description of how to restart an offload operation.