Hi,
Sometimes You can get “RMAN-20001: target database not found in recovery catalog ” error.
Details of error are as follows.
RMAN-20001: target database not found in recovery catalog
Cause: target database is not found in the recovery catalog
Action: make sure that the target database is registered in the recovery recovery catalog
RMAN-03014: implicit resync of recovery catalog failed RMAN-06004: ORACLE error from recovery catalog database: RMAN-20001: target database not found in recovery catalog
This error is related with the target database not being registered to the Catalog database.To solve this error, connect to the catalog database and register the target database as follows.
RMAN> connect catalog user/pwd@CATALOG_DB RMAN> connect target /
Now try to register database again.
RMAN> register database; database registered in recovery catalog starting full resync of recovery catalog full resync complete
Do you want to learn more details about RMAN, then read the following articles.
https://ittutorial.org/rman-backup-restore-and-recovery-tutorials-for-beginners-in-the-oracle-database/