When upgrading Rdb you can do so while journaling is enabled and there is live data in the journals. JCC believes that doing this is a very bad practice. Instead, one should backup the journals prior to performing the upgrade and then again immediately after the upgrade.
The reason this is a bad practice is that any version of Rdb can manage and recover and LogMine journals written only by that version. Having mixed version data in the journals will lead to confusion, potentially inaccessible journals and severe DBA frustration as “old” journals become inaccessible to Rdb and RMU backup. Some customers have found it necessary to actually shut down the application to make the necessary database changes to get control of the situation.
After completing your database upgrade before restarting the application and Loader session, backup the journals with a quiet point backup and modify your loader session to restart its work from the live journals and ignore any older backup AIJs that it would normally encounter. This is documented in the section titled “Overrides in the Run Command”. Basically you would add “checkpoint live” to the JCC_RUN_CLM_LML command.
Be absolutely sure you remove this checkpoint live after restarting so you do not accidentally skip data at some future time.