Data Guard Check up Commands

 1) Basic information of database (primary or standby)

SQL> SELECT DATABASE_ROLE, DB_UNIQUE_NAME INSTANCE, OPEN_MODE, PROTECTION_MODE, PROTECTION_LEVEL, SWITCHOVER_STATUS FROM V$DATABASE;

2) Check for messages/errors

SQL> SELECT MESSAGE FROM V$DATAGUARD_STATUS;

3) To display current status information for specific physical standby database background processes.

SQL> SELECT PROCESS, STATUS, THREAD#, SEQUENCE#, BLOCK#, BLOCKS FROM V$MANAGED_STANDBY ;

4) Show received archived logs on physical standby -Run this query on physical standby

SQL> select registrar, creator, thread#, sequence#, first_change#, next_change# from v$archived_log;

5) To check the log status

 select 'Last Log applied : ' Logs, to_char(next_time,'DD-MON-YY:HH24:MI:SS') Time
from v$archived_log
where sequence# = (select max(sequence#) from v$archived_log where applied='YES')
union
select 'Last Log received : ' Logs, to_char(next_time,'DD-MON-YY:HH24:MI:SS') Time
from v$archived_log
where sequence# = (select max(sequence#) from v$archived_log);

6) To display various information about the redo data. This includes redo data generated by the primary database that is not yet available on the standby database and how much redo has not yet been applied to the standby database.

set lines 132
col value format a20
SQL> select name, value from V$DATAGUARD_STATS;

7) to monitor efficient recovery operations as well as to estimate the time required to complete the current operation in progress:

SQL> select to_char(start_time, 'DD-MON-RR HH24:MI:SS') start_time,
item, round(sofar/1024,2) "MB/Sec"
from v$recovery_progress
where (item='Active Apply Rate' or item='Average Apply Rate');

8) To find last applied log

SQL> select to_char(max(FIRST_TIME),'hh24:mi:ss dd/mm/yyyy') FROM V$ARCHIVED_LOG where applied='YES';

9) To see if standby redo logs have been created. The standby redo logs should be the same size as the online redo logs. There should be (( # of online logs per thread + 1) * # of threads) standby redo logs. A value of 0 for the thread# means the log has never been allocated.

SQL> SELECT thread#, group#, sequence#, bytes, archived, status FROM v$standby_log order by thread#, group#;

10) To produce a list of defined archive destinations. It shows if they are enabled, what process is servicing that destination, if the destination is local or remote, and if remote what the current mount ID is. For a physical standby we should have at least one remote destination that points the primary set.

column destination format a35 wrap
column process format a7
column ID format 99
column mid format 99
SQL> SELECT thread#, dest_id, destination, gvad.status, target, schedule, process, mountid mid FROM gv$archive_dest gvad, gv$instance gvi WHERE gvad.inst_id = gvi.inst_id AND destination is NOT NULL ORDER BY thread#, dest_id;

11) Verify the last sequence# received and the last sequence# applied to standby database.

SQL> SELECT al.thrd "Thread", almax "Last Seq Received", lhmax "Last Seq Applied" FROM (select thread# thrd, MAX(sequence#) almax FROM v$archived_log WHERE resetlogs_change#=(SELECT resetlogs_change# FROM v$database) GROUP BY thread#) al, (SELECT thread# thrd, MAX(sequence#) lhmax FROM v$log_history WHERE resetlogs_change#=(SELECT resetlogs_change# FROM v$database) GROUP BY thread#) lh WHERE al.thrd = lh.thrd;

Comments

Post a Comment

Popular posts from this blog

Cold Backup Cloning of Database .

 Cold Backup :  A cold backup is done when there is no user activity going on with the system. Also called as offline backup, is taken when the database is not running and no users are logged in. all files of the database are copied and no changes during the copy are made. Cold backup can be preformed when Database is in archive mode as well as Non archive log mode  . Backup Strategy :  Gather all the details of physical files (CRD) files in  database . redo log files are online redo log and archived redo log ones .   Select file_name,tablespace_name from dba_data_files  ; select * from v$controlfile  select member from v$logfile ; select name from v$archived_Log ;  create pfile from spfile  Backup  the contol file manually . alter database backup controlfile to trace as '/tmp/coldbackup_controlfile.sql' ;     Stop all the DB services (Database ,Listener)on source DB Server. Copy all the files(Datafiles,redologfiles,pfile,contol file backup) from source to backup location 
Read more

Find ALert log Location

 The alert log is an XML file that is a the log of messages and errors. Each alert log is specific to its component type, such as database, Oracle ASM, listener, and Oracle Clusterware. For the database, the alert log includes messages about the following:     Critical errors (incidents)     Administrative operations, such as starting up or shutting down the database,         recovering the database, creating or dropping a tablespace, and others.     Errors during automatic refresh of a materialized view     Other database events      Trace files are updated periodically over the life of the process and can contain information on the process environment,  status, activities, and errors. In addition, when a process detects a critical error,  it writes information about the error to its trace file.      Using Find Command    find $ORACLE_BASE -type f -name alert_$ORACLE_SID.log    select value from GV$DIAG_INFO WHERE name='Diag Trace';    find /opt/oracle -name alert*log
Read more

FRA Usage and Administration

Image
 In Oracle database, the Flash Recovery Area or FRA is a location on disk where the database can create and manage several kinds of backup and recovery-related files. Main file types are archivelog, flashback log, backups, as well as mirrors for your control files and redo log files. All files in the FRA are Oracle-managed files. Using a Flash Recovery Area simplifies the administration of your database by automatically retaining them for as long as they are needed for restore and recovery activities, and deleting them when they are no longer needed, because the space is needed for another backup and recovery-related purpose. Checking the current usage  You can check the configuration by looking at two parameters.The parameters are db_receovery_file_dest and second one db_recovery_file_dest_size .  db_receovery_file_dest point to location where the files will be located in Server . FOr normal single Databases this will be any directory for RAC this will be set to a Diskgroup whi
Read more