Scripts to resize standby redolog files
Posted by John Hallas on February 28, 2011
I have already posted about an issue that required me to drop and recreate standby log files so I thought I would post the scripts I used.
Resize Standby Redo Logs
1. On primary defer log shipping (dynamic change)
alter system set log_archive_dest_state_2 = defer scope = memory;
2. On standby database cancel managed recovery
alter database recover managed standby database cancel;
3. Drop standby logs on standby database
ALTER DATABASE DROP STANDBY LOGFILE GROUP 4; ALTER DATABASE DROP STANDBY LOGFILE GROUP 5; ALTER DATABASE DROP STANDBY LOGFILE GROUP 6; ALTER DATABASE DROP STANDBY LOGFILE GROUP 7;
4. Recreate the new Standby logs
alter database add standby logfile THREAD 1 group 4 ('+DATA(ONLINELOG)','+FRA(ONLINELOG)') SIZE 1000M;
alter database add standby logfile THREAD 1 group 5 ('+DATA(ONLINELOG)','+FRA(ONLINELOG)') SIZE 1000M;
alter database add standby logfile THREAD 1 group 6 ('+DATA(ONLINELOG)','+FRA(ONLINELOG)') SIZE 1000M;
alter database add standby logfile THREAD 1 group 7 ('+DATA(ONLINELOG)','+FRA(ONLINELOG)') SIZE 1000M;
5. Enable log shipping on the Primary database
alter system set log_archive_dest_state_2 = enable scope = memory;
6. Enable managed recovery on standby database
alter database recover managed standby database using current logfile disconnect;
7. Check the the standby logs are being used by running following query :
set lines 155 pages 9999 col thread# for 9999990 col sequence# for 999999990 col grp for 990 col fnm for a50 head "File Name" col "Fisrt SCN Number" for 999999999999990 break on thread # skip 1 select a.thread# ,a.sequence# ,a.group# grp , a.bytes/1024/1024 Size_MB ,a.status ,a.archived ,a.first_change# "First SCN Number" ,to_char(FIRST_TIME,'DD-Mon-RR HH24:MI:SS') "First SCN Time" ,to_char(LAST_TIME,'DD-Mon-RR HH24:MI:SS') "Last SCN Time" from v$standby_log a order by 1,2,3,4 /
Should return the following :
THREAD# SEQUENCE# GRP SIZE_MB STATUS ARC Fisrt SCN Number First SCN Time Last SCN Time -------- ---------- ---- ---------- ---------- --- ---------------- --------------------------- --------------------------- 1 0 4 100 UNASSIGNED NO 0 0 6 100 UNASSIGNED YES 0 0 7 100 UNASSIGNED YES 0 7316 5 100 ACTIVE YES 153517071 04-Feb-11 13:39:32 04-Feb-11 13:40:41
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venkat said
Do you have the standby_file_management set to ‘AUTO’ in order to follow the above approach
John Hallas said
Yes we do have it set to AUTO. Sorry for the delay in replying
John