Oracle DG主备架构下归档日志删除方案

mahan

一、使用RMAN配置两种删除策略
11g以后，归档日志的删除策略可以配置如下两种：

CONFIGURE ARCHIVELOG DELETION POLICY TO SHIPPED ON ALL STANDBY;
CONFIGURE ARCHIVELOG DELETION POLICY TO APPLIED ON ALL STANDBY;
说明：

1、需要在rman中进行配置rman target /
2、POLICY TO SHIPPED ON ALL STANDBY表示归档日志必须已经传输到所有备库主机，才能删除对应的归档日志；
3、POLICY TO APPLIED ON ALL STANDBY表示归档日志已经传输到所有备库主机，并且备库上必须应用完归档日志，才能删除对应的归档日志；

总结：
1、上述两种配置，可以确认归档日志传输至备库以后才可以被删除。
2、推荐使用 TO APPLIED ON ALL STANDBY这个！！另外一个出现过bug问题。

案例说明，如果备库未应用，主库归档日志删除时，报错如下

RMAN> delete archivelog all;
released channel: ORA_DISK_1
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=45 device type=DISK
RMAN-08120: WARNING: archived log not deleted, not yet applied by standby
archived log file name=/oradata/arch/1_52_1236681669.dbf thread=1 sequence=52
二、主备架构下，主库归档日志删除方案
特别注意：如果主备异常，情况一直未被发现或者处理，主库的归档日志可能越积越多，最终撑爆归档目录，进一步主库数据库无法使用。

（一）主库归档日志的删除方案如下
1、rman配置归档日志删除策略（主库上执行）

rman target /
CONFIGURE ARCHIVELOG DELETION POLICY TO APPLIED ON ALL STANDBY;
2、归档日志备份和删除策略

backup  format  '/backup/xxxx_arch_%T_%s_%p_%t' archivelog all delete input;  
备注：备份完成的归档文件，备份完立刻删除掉
3、主库归档日志定时删除任务（强制删除N天以前的归档日志），防止归档日志撑爆的问题

delete noprompt FORCE archivelog all completed before 'sysdate-3';
（二）主库归档日志定时删除任务案例，强制删除3天以前的归档日志，不管备库是否接受和应用！
1）创建归档日志强制删除脚本
su - oracle
mkdir  /home/oracle/scripts
vi /home/oracle/scripts/delete_arch.sh
#!/bin/bash
source /home/oracle/.bash_profile
DTIME=`date +%Y%m%d%H%M%S`
log=/home/oracle/scripts/${DTIME}.log
date > ${log}
rman target / nocatalog  log=${log} append    <<EOF
delete noprompt FORCE archivelog all completed before 'sysdate-3';
exit
EOF
2）脚本权限修改
chmod 775 /home/oracle/scripts/delete_arch.sh
3)验证
ll /home/oracle/scripts/delete_arch.sh
-rwxrwxr-x 1 oracle oinstall 247 Jun 29 16:53 /home/oracle/scripts/delete_arch.sh
4）制定crontab定时任务
crontab -e
30 5 * * *  /home/oracle/scripts/delete_arch.sh >>/home/oracle/scripts/delete_arch.out 2>&1
每天早上5点30分，运行/home/oracle/delete_arch.sh脚本，删除符合条件的归档日志文件
三、主备架构下，备库归档日志删除方案
特别注意：备库的归档日志，不会随着主库删除而删除，需要单独制定备库归档日志文件的删除策略！！

备库归档日志删除方案：
1）rman配置归档日志删除策略，即POLICY TO APPLIED ON ALL STANDBY；
2）备库建立归档日志定时删除任务（强制删除N天以前的归档日志），防止归档日志撑爆的问题。

（一）备库归档日志删除策略
1、rman配置归档日志删除策略（备库上执行）

rman target /
CONFIGURE ARCHIVELOG DELETION POLICY TO APPLIED ON ALL STANDBY;
2、错误案例，如果归档日志备库还未应用，则备库删除归档日志时，报错如下

RMAN> delete archivelog all;
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=36 device type=DISK
RMAN-08120: WARNING: archived log not deleted, not yet applied by standby
archived log file name=/oradata/arch/1_52_1236681669.dbf thread=1 sequence=52
RMAN-08120: WARNING: archived log not deleted, not yet applied by standby
archived log file name=/oradata/arch/1_53_1236681669.dbf thread=1 sequence=53
List of Archived Log Copies for database with db_unique_name ORCL_ST
=====================================================================
Key     Thrd Seq     S Low Time
------- ---- ------- - ---------
1       1    51      A 29-JUN-26
        Name: /oradata/arch/1_51_1236681669.dbf

Do you really want to delete the above objects (enter YES or NO)? yes
deleted archived log
archived log file name=/oradata/arch/1_51_1236681669.dbf RECID=1 STAMP=1237216215
Deleted 1 objects
（二）备库归档日志定时删除任务案例，强制删除3天以前的归档日志，不管备库是否接受和应用！
1）创建归档日志强制删除脚本
su - oracle
mkdir  /home/oracle/scripts
vi /home/oracle/scripts/delete_arch.sh
#!/bin/bash
source /home/oracle/.bash_profile
DTIME=`date +%Y%m%d%H%M%S`
log=/home/oracle/scripts/${DTIME}.log
date > ${log}
rman target / nocatalog  log=${log} append    <<EOF
delete noprompt FORCE archivelog all completed before 'sysdate-3';
exit
EOF
2）脚本权限修改
chmod 775 /home/oracle/scripts/delete_arch.sh
3)验证
ll /home/oracle/scripts/delete_arch.sh
-rwxrwxr-x 1 oracle oinstall 247 Jun 29 16:53 /home/oracle/scripts/delete_arch.sh
4）制定crontab定时任务
crontab -e
30 5 * * *  /home/oracle/scripts/delete_arch.sh >>/home/oracle/scripts/delete_arch.out 2>&1
每天早上5点30分，运行/home/oracle/delete_arch.sh脚本，删除符合条件的归档日志文件