【11GR2 RAC】如何开启归档和FLASHBACK

刚装好11GR2?RAC一般需要将数据库置于归档模式，并且enable flashback database。

这个步骤在以前是需要先设置cluster_database=false的，但11GR2已经变得非常简单，就跟我们操作单实例是一样的了。赞一下。

下面是一个例子，我将归档日志也放在了ASM上，RACTEST1的归档放在+DATA/ARC1下，RACTEST2的归档放到+DATA/ARC2下。

而Flashbask area是需要单独的一个disk group的，所以特地给他创建了个新的DG -- HAOFLASH。

1. under ASM env:

SQL> conn / as sysasm
Connected.

SQL> CREATE DISKGROUP haoflash
? 2??? EXTERNAL REDUNDANCY
? 3??? DISK '/dev/raw/raw3';

Diskgroup created.

SQL> ALTER DISKGROUP?data?add directory '+DATA/ARC1';

Diskgroup altered.

SQL> ALTER DISKGROUP data add directory '+DATA/ARC2';

2. under?ORACLE?env:

SQL> alter system set log_archive_dest_1='location=+DATA/ARC1' scope=spfile sid='RACTEST1';

System altered.

SQL> alter system set log_archive_dest_1='location=+DATA/ARC2' scope=spfile sid='RACTEST2';

SQL> alter system set db_recovery_file_dest_size = 4G scope=both sid='*';

SQL> alter system set db_recovery_file_dest = '+HAOFLASH' scope=both sid='*';

SQL> alter system set db_flashback_retention_target = 1440 scope=both sid='*';

3. shutdown all instances:

on racnode1:
SQL>? shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.

[oracle@racnode1 raw]$ srvctl status database -d RACTEST
Instance RACTEST1 is not running on node racnode1
Instance RACTEST2 is running on node racnode2

on racnode2:
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.

这时可以看到节点2已经down了。

[oracle@racnode2 ~]$ srvctl status database -d RACTEST
Instance RACTEST1 is not running on node racnode1
Instance RACTEST2 is not running on node racnode2

[oracle@racnode2 ~]$ crs_stat -t -v|grep db
ora.ractest.db ora....se.type 0/2??? 0/1??? OFFLINE?? OFFLINE?

4.start mount one instance(eg,racnode1) and enable ARCHIVELOG and FLASHBACK

SQL> startup mount
ORACLE instance started.

Total System Global Area? 849530880 bytes
Fixed Size????????????????? 1339824 bytes
Variable Size???????????? 650120784 bytes
Database Buffers????????? 192937984 bytes
Redo Buffers??????????????? 5132288 bytes
Database mounted.

SQL> alter database archivelog;

Database altered.

SQL> alter database flashback on;

SQL> SELECT LOG_MODE,FLASHBACK_ON FROM V$DATABASE;

LOG_MODE???? FLASHBACK_ON
------------ ------------------
ARCHIVELOG?? YES

SQL> alter database open;

5.startup other instances

[oracle@racnode2 ~]$ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.1.0 Production on Thu Jun 24 16:37:52 2010

Copyright (c) 1982,2009,Oracle.? All rights reserved.

Connected to an idle instance.

SQL> startup
ORACLE instance started.

Total System Global Area? 849530880 bytes
Fixed Size????????????????? 1339824 bytes
Variable Size???????????? 654315088 bytes
Database Buffers????????? 188743680 bytes
Redo Buffers??????????????? 5132288 bytes
Database mounted.
Database opened.

[oracle@racnode1 raw]$ crs_stat -t -v|grep db
ora.ractest.db ora....se.type 0/2??? 0/1??? ONLINE??? ONLINE??? racnode1?

[oracle@racnode1 raw]$ srvctl status database -d RACTEST
Instance RACTEST1 is running on node racnode1
Instance RACTEST2 is running on node racnode2

6.verify

on racnode1:
SQL> archive log list
Database log mode????????????? Archive Mode
Automatic archival???????????? Enabled
Archive destination??????????? +DATA/arc2
Oldest online log sequence???? 11
Next log sequence to archive?? 12
Current log sequence?????????? 12

on racnode2:
SQL> archive log list
Database log mode????????????? Archive Mode
Automatic archival???????????? Enabled
Archive destination??????????? +DATA/arc2
Oldest online log sequence???? 11
Next log sequence to archive?? 12
Current log sequence?????????? 12

SQL> alter system switch logfile;

SQL> archive log list
Database log mode????????????? Archive Mode
Automatic archival???????????? Enabled
Archive destination??????????? +DATA/arc2
Oldest online log sequence???? 12
Next log sequence to archive?? 13
Current log sequence?????????? 13

SQL>? select THREAD#,SEQUENCE#,ARCHIVED from? v$archived_log;

?? THREAD#? SEQUENCE# ARC
---------- ---------- ---
???????? 2???????? 11 YES
???????? 2???????? 12 YES
????????
on racnode1:

SQL> select THREAD#,255)">?? THREAD#? SEQUENCE# ARC ---------- ---------- --- ???????? 2???????? 11 YES ???????? 2???????? 12 YES ???????? 1???????? 13 YES