We have a requirement to take special month end backups at 9pm to retain for 90 days separate from our standard weekly level 0, nightly level 1 (both of which run at 1am), and multi day archive log backups (running every 15 minutes) of our Oracle 19c two-node RAC database. I am using the following command to initiate the special backups:
backup database plus archivelog keep until time 'sysdate + 90';
Upon examining the RMAN backup list, however, while it appears the archivelog backups associated with this command are being retained for 90 days, the full backup initiated with this command is not being given a keep time and is being obsoleted based on our standard retention period which is 30 days. I can manually change the keep time for the database backup tag after the fact, but what syntax would accomplish this automatically?