验证DG最大性能模式下使用ARCH/LGWR及STANDBY LOG的不同情况
总结: --两台单实例数据库做DG,数据库版本10.2.0.1.0
1.主库配置为:arch async,备库无STANDBY LOG。
日志中会有:RFS[4]: No standby redo logfiles created
2.主库配置为:arch async,备库有STANDBY LOG,日志中未显示使用。
特殊情况:主库配置为:arch async,,备库有STANDBY LOG,备库未打开日志应用 ,日志中有:RFS[8]: Successfully opened standby log 4: '/u01/app/Oracle/prod/disk1/standbylog1.log'
3.主库修改参数为:lgwr async,备库有STANDBY LOG,日志如下:
RFS[10]: Successfully opened standby log 4: '/u01/app/oracle/prod/disk1/standbylog1.log'
4.主库修改参数为:log_archive_dest_2 == SERVICE=PROD,只写SERVICE=PROD主库归档不能传送到备库。
1.主库配置及日志:
主库:
SQL> select protection_mode,database_role,protection_level from v$database;
PROTECTION_MODE DATABASE_ROLE PROTECTION_LEVEL
-------------------- ---------------- --------------------
MAXIMUM PERFORMANCE PRIMARY MAXIMUM PERFORMANCE
15:47:43 SQL> show parameter log_archive_dest_2
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
log_archive_dest_2 string SERVICE=prod1 arch async VALI
D_FOR=(ONLINE_LOGFILES,PRIMARY
_ROLE) DB_UNIQUE_NAME=prod1
15:47:49 SQL> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
27
备库:
SQL> select protection_mode,database_role,protection_level from v$database;
PROTECTION_MODE DATABASE_ROLE PROTECTION_LEVEL
-------------------- ---------------- --------------------
MAXIMUM PERFORMANCE PHYSICAL STANDBY MAXIMUM PERFORMANCE
03:48:02 SQL> select group#,thread#,bytes/1024/1024 mb,status from v$standby_log;
no rows selected
03:48:05 SQL> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
27
####################
2.主库做REDO日志切换并查看日志:
15:48:18 SQL> alter system switch logfile;
System altered.
15:49:33 SQL> alter system switch logfile;
System altered.
15:50:11 SQL> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
29
备库已经接收:
03:49:48 SQL> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
29
主库日志:
[oracle@ocm1 ~]$ tail -f alert_PROD.log
Sun Apr 20 15:49:33 2014
Thread 1 advanced to log sequence 29
Current log# 2 seq# 29 mem# 0: /u01/app/oracle/prod/disk1/redo02.log
Current log# 2 seq# 29 mem# 1: /u01/app/oracle/prod/disk2/log2b.log
Sun Apr 20 15:50:11 2014
Thread 1 advanced to log sequence 30
Current log# 3 seq# 30 mem# 0: /u01/app/oracle/prod/disk1/redo03.log
Current log# 3 seq# 30 mem# 1: /u01/app/oracle/prod/disk2/log3b.log
备库日志:
[oracle@ocm2 ~]$ tail -f alert_PROD1.log
RFS[4]: Archived Log: '/u01/app/oracle/prod/arch/1_28_844894247.arc'
Sun Apr 20 03:49:30 2014
Media Recovery Log /u01/app/oracle/prod/arch/1_28_844894247.arc
Media Recovery Waiting for thread 1 sequence 29
Sun Apr 20 03:50:07 2014
RFS[4]: No standby redo logfiles created
RFS[4]: Archived Log: '/u01/app/oracle/prod/arch/1_29_844894247.arc'
Sun Apr 20 03:50:10 2014
Media Recovery Log /u01/app/oracle/prod/arch/1_29_844894247.arc
Media Recovery Waiting for thread 1 sequence 30
##########################################################
主库配置不变。
备库增加STANDBY LOG:
03:55:04 SQL> alter database recover managed standby database cancel;
Database altered.
03:56:39 SQL> alter database add standby logfile '/u01/app/oracle/prod/disk1/standbylog1.log' size 100m;
Database altered.
03:56:50 SQL> alter database add standby logfile '/u01/app/oracle/prod/disk1/standbylog2.log' size 100m;
Database altered.
03:56:55 SQL> alter database add standby logfile '/u01/app/oracle/prod/disk1/standbylog3.log' size 100m;
Database altered.
03:57:00 SQL> alter database add standby logfile '/u01/app/oracle/prod/disk1/standbylog4.log' size 100m;
Database altered.
03:57:05 SQL> select group#,thread#,bytes/1024/1024 mb,status from v$standby_log;
GROUP# THREAD# MB STATUS
---------- ---------- ---------- ----------
4 0 100 UNASSIGNED
5 0 100 UNASSIGNED
6 0 100 UNASSIGNED
7 0 100 UNASSIGNED
04:13:33 SQL> alter database recover managed standby database disconnect from session;
Database altered.
04:14:12 SQL> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
38
###在主库切换日志:
16:15:40 SQL> alter system switch logfile;
System altered.
16:15:53 SQL> alter system switch logfile;
System altered.
16:16:10 SQL> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
40
备库查询:
04:02:47 SQL> select max(sequence#) from v$archived_log;
MAX(SEQUENCE#)
--------------
32
04:02:49 SQL>
############################
第二次正常时的日志:
[oracle@ocm1 ~]$ tail -f alert_PROD.log
Sun Apr 20 16:18:21 2014
Thread 1 cannot allocate new log, sequence 42
Checkpoint not complete
Current log# 2 seq# 41 mem# 0: /u01/app/oracle/prod/disk1/redo02.log
Current log# 2 seq# 41 mem# 1: /u01/app/oracle/prod/disk2/log2b.log
Thread 1 advanced to log sequence 42
Current log# 3 seq# 42 mem# 0: /u01/app/oracle/prod/disk1/redo03.log
Current log# 3 seq# 42 mem# 1: /u01/app/oracle/prod/disk2/log3b.log
Sun Apr 20 16:19:08 2014
Thread 1 cannot allocate new log, sequence 43
Checkpoint not complete
Current log# 3 seq# 42 mem# 0: /u01/app/oracle/prod/disk1/redo03.log
Current log# 3 seq# 42 mem# 1: /u01/app/oracle/prod/disk2/log3b.log
Thread 1 advanced to log sequence 43
Current log# 1 seq# 43 mem# 0: /u01/app/oracle/prod/disk1/redo01.log
Current log# 1 seq# 43 mem# 1: /u01/app/oracle/prod/disk2/log1b.log
Sun Apr 20 16:20:41 2014
Expanded controlfile section 11 from 56 to 112 records
Requested to grow by 56 records; added 2 blocks of records
备库:
[oracle@ocm2 ~]$ tail -f alert_PROD1.log
Sun Apr 20 04:20:36 2014
Redo Shipping Client Connected as PUBLIC
-- Connected User is Valid
RFS[8]: Assigned to RFS process 16069
RFS[8]: Identified database type as 'physical standby'
RFS[8]: Archived Log: '/u01/app/oracle/prod/arch/1_40_844894247.arc'
RFS[8]: Archived Log: '/u01/app/oracle/prod/arch/1_41_844894247.arc'
RFS[8]: Archived Log: '/u01/app/oracle/prod/arch/1_42_844894247.arc'
Sun Apr 20 04:20:37 2014
Media Recovery Log /u01/app/oracle/prod/arch/1_40_844894247.arc
Media Recovery Log /u01/app/oracle/prod/arch/1_41_844894247.arc
Media Recovery Log /u01/app/oracle/prod/arch/1_42_844894247.arc
Media Recovery Waiting for thread 1 sequence 43
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