Cancel the MRP process and run the query below with sqlplus to find the required sequence.
SQL > alter database recover managed standby database cancel;
Check the archivelog required to recover the standby DB.
SQL> alter database recover standby database;============
alter database recover standby database
*
ERROR at line 1:
ORA-00279: change 76791978408 generated at 12/01/2022 08:13:07 needed for
thread 1
ORA-00289: suggestion : +RECOC1
ORA-00280: change 76791978408 for thread 1 is in sequence #432918
SQL>
==================Step 02.
In this scenario, thread 1 sequence 432918 is required to recover.
Check the max sequence generated on Primary database.
SQL> select max(SEQUENCE#),thread# from v$archived_log
group by thread#;
Run the RMAN command below to take the backup accordingly.
RMAN > BACKUP AS COMPRESSED BACKUPSET ARCHIVELOG FROM SEQUENCE 432918 UNTIL SEQUENCE 433570 THREAD 1 format '/mnt/nfs/Ora_back/RMAN/DBM01/%U';
Step 03.
Copy the Backup files to the Standby database server.
Step 04.
Catalog the backup files.
RMAN> catalog start with '/acfs01/Ora_back/RMAN/DBM01/Arc_T1';
Step 05.
Recover the database.
RMAN> recover database;
--- Got below error as I've to take a thread 2 backup as well because this is a RAC Database.
RMAN-06054: media recovery requesting unknown archived log for thread 2 with sequence 545051 and starting SCN of 7679200924
------
Step 06.
Take the backup of thread 2.
RMAN > BACKUP AS COMPRESSED BACKUPSET ARCHIVELOG FROM SEQUENCE 545051 UNTIL SEQUENCE 545510 THREAD 2 format '/mnt/nfs/Ora_back/RMAN/DBM01/%U';
Step 07.
Copy the Files and Catalog again as thread 1.
Step 08.
RMAN> recover database;
SQL > alter database recover managed standby database disconnect from session;