Script to Collect Data Guard Physical Standby Diagnostic Information [ID 241438.1]

Posted By Sagar Patil

I generally don’t cut and paste metalink notes. But in case you are using DG , for diagnosis you will have to use 2 metalink scripts, [ID 241438.1] & [ID 241374.1]

Script to Collect Data Guard Physical Standby Diagnostic Information [ID 241438.1]
 Modified 20-APR-2011     Type SCRIPT     Status PUBLISHED      
This script is intended to provide an easy method to provide information
necessary to troubleshoot Data Guard issues.

-- NAME: DG_phy_stby_diag.sql    
-- ------------------------------------------------------------------------ 
-- AUTHOR:  
--    Michael Smith - Oracle Support Services - DataServer Group
--    Copyright 2002, Oracle Corporation      
-- ------------------------------------------------------------------------ 
--    This script is to be used to assist in collection information to help
--    troubeshoot Data Guard issues.
-- ------------------------------------------------------------------------ 
--    This script is provided for educational purposes only. It is NOT  
--    supported by Oracle World Wide Technical Support. 
--    The script has been tested and appears to work as intended. 
--    You should always run new scripts on a test instance initially. 
-- ------------------------------------------------------------------------ 
-- Script output is as follows:

set echo off
set feedback off
column timecol new_value timestamp
column spool_extension new_value suffix
select to_char(sysdate,'Mondd_hhmi') timecol,
'.out' spool_extension from sys.dual;
column output new_value dbname
select value || '_' output
from v$parameter where name = 'db_name';
spool dgdiag_phystby_&&dbname&&timestamp&&suffix
set lines 200
set pagesize 35
set trim on
set trims on
alter session set nls_date_format = 'MON-DD-YYYY HH24:MI:SS';
set feedback on
select to_char(sysdate) time from dual;

set echo on

-- ARCHIVER can be  (STOPPED | STARTED | FAILED) FAILED means that the archiver failed
-- to archive a -- log last time, but will try again within 5 minutes. LOG_SWITCH_WAIT
-- The ARCHIVE LOG/CLEAR LOG/CHECKPOINT event log switching is waiting for. Note that 
-- if ALTER SYSTEM SWITCH LOGFILE is hung, but there is room in the current online 
-- redo log, then value is NULL 

column host_name format a20 tru
column version format a9 tru
select instance_name,host_name,version,archiver,log_switch_wait from v$instance;

-- The following select will give us the generic information about how this standby is
-- setup.  The database_role should be standby as that is what this script is intended 
-- to be ran on.  If protection_level is different than protection_mode then for some
-- reason the mode listed in protection_mode experienced a need to downgrade.  Once the
-- error condition has been corrected the protection_level should match the protection_mode
-- after the next log switch.

column ROLE format a7 tru
select name,platform_id,database_role role,log_mode,
 flashback_on flashback,protection_mode,protection_level 
from v$database;

-- Force logging is not mandatory but is recommended.  Supplemental logging should be enabled
-- on the standby if a logical standby is in the configuration. During normal 
-- operations it is acceptable for SWITCHOVER_STATUS to be SESSIONS ACTIVE or NOT ALLOWED.

column force_logging format a13 tru
column remote_archive format a14 tru
column dataguard_broker format a16 tru
select force_logging,remote_archive,supplemental_log_data_pk,supplemental_log_data_ui,
switchover_status,dataguard_broker from v$database; 

-- This query produces a list of all archive destinations and 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 but it should be deferred.

COLUMN destination FORMAT A35 WRAP
column process format a7
column archiver format a8
column ID format 99

select dest_id "ID",destination,status,target,
from v$archive_dest;

-- If the protection mode of the standby is set to anything higher than max performance
-- then we need to make sure the remote destination that points to the primary is set
-- with the correct options else we will have issues during switchover.

select dest_id,process,transmit_mode,async_blocks,
from v$archive_dest;

-- The following select will show any errors that occured the last time an attempt to
-- archive to the destination was attempted.  If ERROR is blank and status is VALID then
-- the archive completed correctly.

column error format a55 tru
select dest_id,status,error from v$archive_dest;

-- Determine if any error conditions have been reached by querying thev$dataguard_status
-- view (view only available in 9.2.0 and above):

column message format a80
select message, timestamp
from v$dataguard_status
where severity in ('Error','Fatal')
order by timestamp;

-- The following query is ran to get the status of the SRL's on the standby.  If the
-- primary is archiving with the LGWR process and SRL's are present (in the correct
-- number and size) then we should see a group# active.

select group#,sequence#,bytes,used,archived,status from v$standby_log;

-- The above SRL's should match in number and in size with the ORL's returned below:

select group#,thread#,sequence#,bytes,archived,status from v$log;

-- Query v$managed_standby to see the status of processes involved in the
-- configuration.

select process,status,client_process,sequence#,block#,active_agents,known_agents
from v$managed_standby;

-- Verify that the last sequence# received and the last sequence# applied to standby
-- database.

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$log_history
 where first_time=(select max(first_time) from v$log_history)
 group by thread#) lh
where al.thrd = lh.thrd;

-- The V$ARCHIVE_GAP fixed view on a physical standby database only returns the next
-- gap that is currently blocking redo apply from continuing. After resolving the
-- identified gap and starting redo apply, query the V$ARCHIVE_GAP fixed view again
-- on the physical standby database to determine the next gap sequence, if there is
-- one.

select * from v$archive_gap;

-- Non-default init parameters.

set numwidth 5
column name format a30 tru
column value format a50 wra
select name, value
from v$parameter
where isdefault = 'FALSE';

spool off

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