How to resolve MRP stuck issues on a physical standby database

How to resolve MRP stuck issues on a physical standby database

On my standby database, one day suddenly redo apply stopped and log files are showing the following error messages. On investigating, found that MRP process not running and doesn't apply more logs

ORA-16766: Redo Apply unexpectedly offline

ORA-00332: archived log is too small - may be incompletely archived

ORA-00334: archived log: <Archive log file name>

MRP stuck issues on a physical standby database

MRP0: Background Media Recovery terminated with error 332

Environment:

10g R2 Single  Instance Database with Dataguard Broker on Linux

I have performed the following activities and was able to restart the redo log apply

Solution:

1.       Verify the size & checksum of the reported archive log between primary and standby database. If they are different, then copy the archive log from primary to standby.  Can use md5sum to verify the checksum.

If the archive log not available you can restore from rman backup as follows

connect target /  catalog=username/pwd@catdb

run {
restore archivelog from logseq=340 until logseq=340 thread=1;
}

2.       Once the file is copied, restart the redo apply service.

Stop the managed recovery and start the manual recovery.

DGMGRL> EDIT DATABASE '<standby db_unique_name>' SET STATE='LOG-APPLY-OFF';
DGMGRL> EDIT DATABASE '<standby db_unique_name>' SET STATE='ONLINE';

3.       Verify the redolog apply started

ps –ef | grep mrp

Adding Standby Redo Log and Resolving Data guard Error

ORA-16801: redo transport-related property is inconsistent with database Settings

Data Guard Setup: Primary with Two Standbys

DB Version: 10.2.0.4.0 64Bit

OS: Enterprise Linux 5.3 64Bit

Data Guard Broker: Yes

Redo Transport Mode: ASYNC

Second standby database created using rman duplicate command. Started the managed recovery process and logs are started applying. Data Guard broker enabled for this database.  While enabling & verifying the configuration for this database, I got the following error.

ORA-16801: redo transport-related property is inconsistent with database setting
ORA-16715: redo transport-related property LogXptMode of standby database "stby2" is inconsistent

Note: I tried to add Standby Redo Log (SRL) immediately after  creating standby but before starting the managed recovery, but I got the error ORA-301 signalled during: ALTER DATABASE ADD STANDBY LOGFILE GROUP  and not able to add the standby redo logs.

I performed the following steps to resolve this issue.

1.       Stop the redo apply on the standby database

ALTER DATABASE RECOVER MANAGED STANDBY DATABASE CANCEL

2.       Create the Standby Redo Log on standby

a) The size of the standby redo log files must match the size of primary database online redo log files. Find the size of the primary database online redo log files. Number of Standby Redo Logs should be at least one greater than number online redo logsSQL> select bytes from v$log;
   BYTES

   ----------

  52428800

  52428800

  52428800
Here the size of my online redo log files is 50M.

b) Use the following query to find the details of the log files in the primary database.

SQL> select group#,type,member from v$logfile;
    GROUP# TYPE    MEMBER

---------- ------- --------------------------------------------------

         1 ONLINE  /u03/oradata/prod_redo01a.log

         1 ONLINE  /u03/oradata/prod_redo01b.log

         2 ONLINE  /u03/oradata/prod_redo02a.log

         2 ONLINE  /u03/oradata/prod_redo02b.log

         3 ONLINE  /u03/oradata/prod_redo03a.log

         3 ONLINE  /u03/oradata/prod_redo03b.log

         4 STANDBY /u03/oradata/prod_redo04a.log

         4 STANDBY /u03/oradata/prod_redo04b.log

         5 STANDBY /u03/oradata/prod_redo05a.log

         5 STANDBY /u03/oradata/prod_redo05b.log

         6 STANDBY /u03/oradata/prod_redo06a.log

    GROUP# TYPE    MEMBER

---------- ------- --------------------------------------------------

         6 STANDBY /u03/oradata/prod_redo06b.log

         7 STANDBY /u03/oradata/prod_redo07a.log

         7 STANDBY /u03/oradata/prod_redo07b.log

From above output you can see that I already have standby redo logs on primary.

c) Now I have created the standby redo log files in the standby database.alter database add standby logfile group 4 ('/u03/oradata/prod_redo04a.log’, '/u03/oradata/prod_redo04b.log’) size 50M ;

alter database add standby logfile group 5 ('/u03/oradata/prod_redo05a.log’, ‘/u03/oradata/oas2/prod_redo05b.log’) size 50M;

alter database add standby logfile group 6 ('/u03/oradata/oas2/prod_redo06a.log’, ‘/u03/oradata/oas2/prod_redo06b.log’) size 50M;

alter database add standby logfile group 7 ('/u03/oradata/oas2/prod_redo07a.log’, ‘/u03/oradata/oas2/prod_redo07b.log’) size 50M;

3.       Start the log apply

SQL> ALTER DATABASE RECOVER MANAGED STANDBY DATABASE DISCONNECT FROM SESSION;

4.     Enable second standby (SSTD)

DGMGRL> enable database stdby2;

5.       Verify the configuration

DGMGRL> show configuration;