Dataguard Setup

Dataguard Setup

Primary Side.

To check how many data guards are configured

Show parameter archive/log

--log_archive_dest1,dest2,dest3 etc….

To check the data guard setup error

select dest_id, dest_name, error from gv$archive_dest; // on primary side

 

show parameter log_archive_dest_state_2

  -- value should be enabled /defer

alter system set log_archive_dest_state_2=defer scope=both;

To remove old archives

rman target /

crosscheck archivelog all

delete archivelog all completed before 'SYSDATE-7';

Standby Side

To check current gap on standby  .We  can use the below query:

SELECT ARCH.THREAD# "Thread", ARCH.SEQUENCE# "Last Sequence Received", APPL.SEQUENCE# "Last Sequence Applied", (ARCH.SEQUENCE# - APPL.SEQUENCE#) "Difference"

FROM

(SELECT THREAD# ,SEQUENCE# FROM V$ARCHIVED_LOG WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME) FROM V$ARCHIVED_LOG GROUP BY THREAD#)) ARCH,

(SELECT THREAD# ,SEQUENCE# FROM V$LOG_HISTORY WHERE (THREAD#,FIRST_TIME ) IN (SELECT THREAD#,MAX(FIRST_TIME) FROM V$LOG_HISTORY GROUP BY THREAD#)) APPL

WHERE

ARCH.THREAD# = APPL.THREAD#

ORDER BY 1;

To check Process status on standby  .We  can use the below query:

select process, status, sequence# from v$managed_standby;

select * from v$bgprocess where NAME like 'MRP%';

  -- MRP process should be applying log/

  -- RFS should be waiing /receiving log

Stop/Start MRP on standby 

 alter database recover managed standby database cancel;

Start:

alter database recover managed standby database disconnect from session;

ALTER DATABASE RECOVER MANAGED STANDBY DATABASE PARALLEL 16 DISCONNECT FROM SESSION;