Configuring Data Guard in 11g using Duplicate

Oracle Solaris SPARC 10u11 Primary: ORACLE_SID: LCM2DBS1 RAC, ASM Standby: ORACLE_SID: LCM2DBS single instance, non-ASM Logging Check that the primary database is in archivelog mode. SELECT force_logging, log_mode FROM v$database; FOR LOG_MODE — ———— YES ARCHIVELOG If it is noarchivelog mode, switch to archivelog mode. SHUTDOWN IMMEDIATE; STARTUP MOUNT; ALTER DATABASE ARCHIVELOG;… Continue reading Configuring Data Guard in 11g using Duplicate

Resolving inactive transaction branch

Recently we encountered wait event ‘invalid transaction branch’ and here is how we resolved it. OS: AIX 7.1 DB: Oracle RAC — identify session waiting for ‘invalid transaction branch’ select sid, serial#, program, machine, sql_id, status, WAIT_TIME_MICRO, event, seconds_in_wait from v$session where username=’ONL1′ and status=’ACTIVE’; 1551 35801 MasterMgmt@PRMBMTR01 (TNS V1-V3) PRMBMTR01 35y99s5k1rjh0 ACTIVE 113572… Continue reading Resolving inactive transaction branch

Simulating voting disk failures

RHEL: 6.6 x86_64 DB: RAC [grid@SCMSDBS05 8540]$ crsctl query css votedisk ## STATE File Universal Id File Name Disk group — —– —————– ——— ——— 1. ONLINE 6d40ce0c73704fbabf8a2a8f73008caa (/dev/mapper/mpath03p1) [OCRDG] 2. ONLINE 1689ccb98f974f0fbf9f174484ec1b37 (/dev/mapper/mpath04p1) [OCRDG] 3. ONLINE 75ce7de14f784f5ebfc67dd08c52fd97 (/dev/mapper/mpath05p1) [OCRDG] Located 3 voting disk(s). [grid@SCMSDBS05 8540]$ dd if=/dev/zero of=/dev/mapper/mpath03p1 dd: writing to `/dev/mapper/mpath03p1′: No… Continue reading Simulating voting disk failures

Steps to recreate standby log files in Data Guard

If the real-time apply feature is enabled, log apply services can apply redo data as it is received, without waiting for the current standby redo log file to be archived. This results in faster switchover and failover times because the standby redo log files have been applied already to the standby database by the time… Continue reading Steps to recreate standby log files in Data Guard

Library cache dump and cursors

Test Environment: Oracle : / RHEL : 6.3 x86_64 sqlplus /nolog conn caoff/caoff drop table TEST_NOT_EXIST purge; drop table TEST_EXIST purge; create table TEST_EXIST as select * from dba_objects where rownum<=10; alter system flush shared_pool; — table TEST_NOT_EXIST does not exist select count(*) from TEST_NOT_EXIST; — table TEST_EXIST exists select count(*) from TEST_EXIST; conn… Continue reading Library cache dump and cursors