RMAN delete information about old backups from the catalog without a tape device

Delete the old entries in the backup catalog with touch the tapes containing the old backups, so we need a ‘dummy channel’ for the tape:

— check how many backups we have
list backup summary;

— create a dummy channel for tape
allocate channel for maintenance device type sbt
parms ‘SBT_LIBRARY=oracle.disksbt, ENV=(BACKUP_DIR=/tmp)’;

— delete entries in catalog from tape backups
report obsolete;
delete obsolete;