运用incremental backup恢复归档GAP的DG-上篇

 

经常听到有DBA因为对DATAGUARD监控不到位，导致归档日志和主库没有同步，更悲剧的是主库通常都设置了RMAN备份，
而全库备份结束后通常会删除归档日志。遇到这种情况，发现很多DBA都会着手重新从主库全库备份恢复到从库，
遇到小的数据库还好，对于动辄上百G或T的库往往会很悲剧，因为数据拷贝时间都相当的漫长。
而事实上对于从库SCN和主库差距并不大，也可以理解为归档差距并不多的DG（比如我们的一个库上线1年了，一个月没有同步差距也不算很大），
根本没必要全库回复，这种情况下增量恢复能快速解决问题，以下是笔者的一次具体操作。

故障现象：
因为周六主库要做历史数据迁移，DBA主动停止了和从库的归档同步。悲剧的是周日凌晨主库有个全库备份动作，
备份完成后把所有的归档都给删除了，这就造成了这部分归档的丢失，从库存在GAP。DBA打算重做DG，申请了一个
晚上8小时的时间，因为数据备份和迁移要5小时，实施和测试计划3小时完成。笔者分析丢失的日志很少，及时制止
了这一实施申请，要求DBA采用incremental recover（增量备份恢复）的方法实现主库和从库同步，
先确定备库的current scn，以此在主库上执行incremental backup，将备份传至备库，使用recover noredo方式恢复备库。
事实证明这种方法是完全可行的。

具体实施如下。

一、实施准备（从库关键数据确认）
1、SPFILE
create pfile='/home/oracle/dba/pfile_before_recover_dg.ora' from spfile;

-rw-r--r-- 1 oracle oinstall 1496 11-14 21:36 pfile_before_recover_dg.ora
drwxr-xr-x 2 oracle oinstall 4096 11-14 21:35 spfile
drwxr-xr-x 2 oracle oinstall 4096 06-01 11:17 expdata
drwxr-xr-x 2 oracle oinstall 4096 2011-04-26 script
[oracle@L-DB-163-18 dba]$ more *.ora
MYPORT.__db_cache_size=3741319168
MYPORT.__java_pool_size=16777216
MYPORT.__large_pool_size=16777216
MYPORT.__shared_pool_size=805306368
MYPORT.__streams_pool_size=0
*.audit_file_dest='/u01/app/oracle/admin/MYPORT/adump'
*.background_dump_dest='/u01/app/oracle/admin/MYPORT/bdump'
*.compatible='10.2.0.3.0'
*.control_files='/u01/datafile/control01.ctl','/u01/datafile/control02.ctl'#Restore Controlfile
*.core_dump_dest='/u01/app/oracle/admin/MYPORT/cdump'
*.db_block_size=8192
*.db_domain=''
*.db_file_multiblock_read_count=32
*.db_file_name_convert='+DATA/MYPORT/datafile','/oradata/datafile'
*.db_name='MYPORT'
*.db_unique_name='standby'
*.dispatchers=''
*.fal_client='STANDBY'
*.fal_server='MYPORT'
*.job_queue_processes=10
*.log_archive_config='DG_CONFIG=(MYPORT,standby)'
*.log_archive_dest_1='LOCATION=/u01/archive valid_for=(all_logfiles,all_roles) db_unique_name=standby'
*.log_archive_dest_2='service=MYPORT lgwr async valid_for=(online_logfiles,primary_role) db_unique_name=MYPORT'
*.log_archive_dest_state_1='ENABLE'
*.log_archive_dest_state_2='ENABLE'
*.log_archive_max_processes=4
*.log_file_name_convert='+DATA/MYPORT/onlinelog','/u01/datafile'
*.open_cursors=1000
*.pga_aggregate_target=1092957696
*.processes=1000
*.remote_login_passwordfile='EXCLUSIVE'
*.sessions=885
*.sga_max_size=4589934592
*.sga_target=4589934592
*.shared_servers=0
*.standby_file_management='AUTO'
*.undo_management='AUTO'
*.undo_tablespace='UNDOTBS1'
*.user_dump_dest='/u01/app/oracle/admin/MYPORT/udump'
[oracle@L-DB-163-18 dba]$

2、查看在线LOG
cd /u01/datafile
[oracle@L-DB-163-18 dba]$ cd /u01/datafile
[oracle@L-DB-163-18 datafile]$ ls -lt
总计 1474052
-rw-r----- 1 oracle oinstall  19873792 11-14 21:39 control01.ctl
-rw-r----- 1 oracle oinstall  19873792 11-14 21:39 control02.ctl
-rw-r----- 1 oracle oinstall 104858112 11-14 21:39 stand03.log
-rw-r----- 1 oracle oinstall 104858112 11-14 21:38 stand01.log
-rw-r----- 1 oracle oinstall 104858112 11-14 20:22 stand02.log
-rw-r----- 1 oracle oinstall 104858112 11-14 18:14 stand04.log
-rw-r----- 1 oracle oinstall 104858112 11-11 02:18 stand05.log
-rw-r----- 1 oracle oinstall 104858112 11-11 02:18 stand06.log
-rw-r----- 1 oracle oinstall  20979712 07-14 04:41 temp01.dbf
-rw-r----- 1 oracle oinstall 104858112 07-14 03:44 group_4.270.697238219
-rw-r----- 1 oracle oinstall 104858112 07-14 03:44 group_4.271.697238221
-rw-r----- 1 oracle oinstall 104858112 07-14 03:44 group_3.268.697238217
-rw-r----- 1 oracle oinstall 104858112 07-14 03:44 group_3.269.697238219
-rw-r----- 1 oracle oinstall 104858112 07-14 03:44 group_2.264.697238179
-rw-r----- 1 oracle oinstall 104858112 07-14 03:44 group_2.265.697238179
-rw-r----- 1 oracle oinstall 104858112 07-14 03:44 group_1.262.697238177
-rw-r----- 1 oracle oinstall 104858112 07-14 03:44 group_1.263.697238177
[oracle@L-DB-163-18 datafile]$

3、查看数据文件
[oracle@L-DB-163-18 datafile]$ cd /oradata/datafile
[oracle@L-DB-163-18 datafile]$ ls -lt
总计 235078392
-rw-r----- 1 oracle oinstall   134225920 11-14 09:20 bbcled_data.588.727381165.dbf
-rw-r----- 1 oracle oinstall 16106135552 11-14 09:20 auditbbc.882.710070905.dbf
-rw-r----- 1 oracle oinstall 13631496192 11-14 09:20 eport_data.522.736786031.dbf
-rw-r----- 1 oracle oinstall   268443648 11-14 09:20 eport_index.779.736786171.dbf
-rw-r----- 1 oracle oinstall 26346135552 11-14 09:20 in_bbc_data.291.730331961.dbf
-rw-r----- 1 oracle oinstall 10737426432 11-14 09:20 in_bbc_data.752.758838665
-rw-r----- 1 oracle oinstall  5368717312 11-14 09:20 in_bbc_index.869.729797303.dbf
-rw-r----- 1 oracle oinstall   536879104 11-14 09:20 inman_data.617.718999513.dbf
-rw-r----- 1 oracle oinstall   134225920 11-14 09:20 inman_index.723.718999521.dbf
-rw-r----- 1 oracle oinstall   268443648 11-14 09:20 in_man_index.885.729797313.dbf
-rw-r----- 1 oracle oinstall 34358697984 11-14 09:20 in_hangzhou_data.362.747696959.dbf
-rw-r----- 1 oracle oinstall 10737426432 11-14 09:20 in_hangzhou_data.740.758652903
-rw-r----- 1 oracle oinstall  8388616192 11-14 09:20 in_hangzhou_index.821.729797323.dbf
-rw-r----- 1 oracle oinstall   104865792 11-14 09:20 in_xian_index.663.747696899.dbf
-rw-r----- 1 oracle oinstall   268443648 11-14 09:20 in_xian_index.724.729797333.dbf
-rw-r----- 1 oracle oinstall 34359730176 11-14 09:20 hangzhou.451.709317119.dbf
-rw-r----- 1 oracle oinstall  2147491840 11-14 09:20 sysaux.257.697238119.dbf
-rw-r----- 1 oracle oinstall  5368717312 11-14 09:20 system.256.697238117.dbf
-rw-r----- 1 oracle oinstall     1056768 11-14 09:20 tbs_catalog.791.752426905.dbf
-rw-r----- 1 oracle oinstall  1073750016 11-14 09:20 tbs_catalog.891.710434097.dbf
-rw-r----- 1 oracle oinstall   209723392 11-14 09:20 ts_test.348.704715437.dbf
-rw-r----- 1 oracle oinstall  7225745408 11-14 09:20 undotbs1.258.697238119.dbf
-rw-r----- 1 oracle oinstall  4294975488 11-14 09:20 undotbs2.267.697238205.dbf
-rw-r----- 1 oracle oinstall 34304827392 11-14 09:20 users.259.697238119.dbf
-rw-r----- 1 oracle oinstall 23571996672 11-14 09:20 users.604.752426949.dbf
-rw-r----- 1 oracle oinstall   536879104 11-14 09:20 xian.880.711538313.dbf

二、实施（从库关键数据确认）

具体步骤为：
1、先确定备库的current scn，以此在主库上执行incremental backup
SQL> select to_char(current_scn) from v$database;

TO_CHAR(CURRENT_SCN)
----------------------------------------
1508381043

SQL> SELECT * FROM V$ARCHIVE_GAP;

   THREAD# LOW_SEQUENCE# HIGH_SEQUENCE#
---------- ------------- --------------
         1         12907          13164
         2         10915          11003

2、在主库执行incremental备份
run
{
allocate channel d1 type disk;
allocate channel d2 type disk;
allocate channel d3 type disk;
allocate channel d4 type disk;
backup as compressed backupset incremental from SCN 1508381043 database format '/u01/rmanbak/for18dg/standby_%d_%T_%U.bak'
include current controlfile for standby filesperset=5  tag 'FOR STANDBY';
release channel d1;
release channel d2;
release channel d3;
release channel d4;
}

--------------------------------------
[oradba@oracle2 for18dg]$ rman target/

Recovery Manager: Release 10.2.0.4.0 - Production on 星期一 11月 14 21:44:27 2011

Copyright (c) 1982, 2007, Oracle.  All rights reserved.

connected to target database: MYPORT (DBID=2649744285)

RMAN> run
{
allocate channel d1 type disk;
allocate channel d2 type disk;
allocate channel d3 type disk;
allocate channel d4 type disk;
backup as compressed backupset incremental from SCN 1508381043 database format '/u01/rmanbak/for18dg/standby_%d_%T_%U.bak'
include current controlfile for standby filesperset=5  tag 'FOR STANDBY';
release channel d1;
release channel d2;
release channel d3;
release channel d4;
}2> 3> 4> 5> 6> 7> 8> 9> 10> 11> 12> 13>

using target database control file instead of recovery catalog
allocated channel: d1
channel d1: sid=909 instance=MYPORT2 devtype=DISK

allocated channel: d2
channel d2: sid=993 instance=MYPORT2 devtype=DISK

allocated channel: d3
channel d3: sid=884 instance=MYPORT2 devtype=DISK

allocated channel: d4
channel d4: sid=886 instance=MYPORT2 devtype=DISK

Starting backup at 2011-11-14 21:44:34
channel d1: starting compressed full datafile backupset
channel d1: specifying datafile(s) in backupset
input datafile fno=00004 name=+DATA/MYPORT/datafile/users.259.697238119
input datafile fno=00001 name=+DATA/MYPORT/datafile/system.256.697238117
input datafile fno=00002 name=+DATA/MYPORT/datafile/undotbs1.258.697238119
channel d1: starting piece 1 at 2011-11-14 21:44:34
channel d2: starting compressed full datafile backupset
channel d2: specifying datafile(s) in backupset
input datafile fno=00024 name=+DATA/MYPORT/datafile/users.604.752426949
input datafile fno=00025 name=+DATA/MYPORT/datafile/in_hangzhou_data.740.758652903
input datafile fno=00014 name=+DATA/MYPORT/datafile/in_bbc_index.869.729797303
channel d2: starting piece 1 at 2011-11-14 21:44:34
channel d3: starting compressed full datafile backupset
channel d3: specifying datafile(s) in backupset
input datafile fno=00009 name=+DATA/MYPORT/datafile/auditbbc.882.710070905
input datafile fno=00019 name=+DATA/MYPORT/datafile/eport_data.522.736786031
input datafile fno=00016 name=+DATA/MYPORT/datafile/in_hangzhou_index.821.729797323
input datafile fno=00021 name=+DATA/MYPORT/datafile/in_xian_index.663.747696899
input datafile fno=00023 name=+DATA/MYPORT/datafile/tbs_catalog.791.752426905
channel d3: starting piece 1 at 2011-11-14 21:44:34
channel d4: starting compressed full datafile backupset
channel d4: specifying datafile(s) in backupset
input datafile fno=00022 name=+DATA/MYPORT/datafile/in_hangzhou_data.362.747696959
input datafile fno=00005 name=+DATA/MYPORT/datafile/undotbs2.267.697238205
input datafile fno=00006 name=+DATA/MYPORT/datafile/ts_test.348.704715437
input datafile fno=00012 name=+DATA/MYPORT/datafile/inman_index.723.718999521
input datafile fno=00013 name=+DATA/MYPORT/datafile/bbcled_data.588.727381165
channel d4: starting piece 1 at 2011-11-14 21:44:34
channel d4: finished piece 1 at 2011-11-14 21:51:10
piece handle=/u01/rmanbak/for18dg/standby_MYPORT_20111114_pamrlq22_1_1.bak tag=FOR STANDBY comment=NONE
channel d4: backup set complete, elapsed time: 00:06:36
channel d4: starting compressed full datafile backupset
channel d4: specifying datafile(s) in backupset
input datafile fno=00007 name=+DATA/MYPORT/datafile/hangzhou.451.709317119
input datafile fno=00003 name=+DATA/MYPORT/datafile/sysaux.257.697238119
input datafile fno=00010 name=+DATA/MYPORT/datafile/tbs_catalog.891.710434097
input datafile fno=00011 name=+DATA/MYPORT/datafile/xian.880.711538313
input datafile fno=00020 name=+DATA/MYPORT/datafile/eport_index.779.736786171
channel d4: starting piece 1 at 2011-11-14 21:51:13
channel d1: finished piece 1 at 2011-11-14 21:53:08
piece handle=/u01/rmanbak/for18dg/standby_MYPORT_20111114_p7mrlq22_1_1.bak tag=FOR STANDBY comment=NONE
channel d1: backup set complete, elapsed time: 00:08:34
channel d1: starting compressed full datafile backupset
channel d1: specifying datafile(s) in backupset
input datafile fno=00018 name=+DATA/MYPORT/datafile/in_bbc_data.291.730331961
input datafile fno=00026 name=+DATA/MYPORT/datafile/in_bbc_data.752.758838665
input datafile fno=00008 name=+DATA/MYPORT/datafile/inman_data.617.718999513
input datafile fno=00015 name=+DATA/MYPORT/datafile/in_man_index.885.729797313
input datafile fno=00017 name=+DATA/MYPORT/datafile/in_xian_index.724.729797333
channel d1: starting piece 1 at 2011-11-14 21:53:10
channel d2: finished piece 1 at 2011-11-14 21:53:45
piece handle=/u01/rmanbak/for18dg/standby_MYPORT_20111114_p8mrlq22_1_1.bak tag=FOR STANDBY comment=NONE
channel d2: backup set complete, elapsed time: 00:09:11
channel d2: starting compressed full datafile backupset
channel d2: specifying datafile(s) in backupset
including standby control file in backupset
channel d2: starting piece 1 at 2011-11-14 21:53:47
channel d2: finished piece 1 at 2011-11-14 21:53:48
piece handle=/u01/rmanbak/for18dg/standby_MYPORT_20111114_pdmrlqj9_1_1.bak tag=FOR STANDBY comment=NONE
channel d2: backup set complete, elapsed time: 00:00:03
channel d4: finished piece 1 at 2011-11-14 21:56:53
piece handle=/u01/rmanbak/for18dg/standby_MYPORT_20111114_pbmrlqee_1_1.bak tag=FOR STANDBY comment=NONE
channel d4: backup set complete, elapsed time: 00:05:43
channel d3: finished piece 1 at 2011-11-14 21:57:08
piece handle=/u01/rmanbak/for18dg/standby_MYPORT_20111114_p9mrlq22_1_1.bak tag=FOR STANDBY comment=NONE
channel d3: backup set complete, elapsed time: 00:12:34
channel d1: finished piece 1 at 2011-11-14 21:59:23
piece handle=/u01/rmanbak/for18dg/standby_MYPORT_20111114_pcmrlqi5_1_1.bak tag=FOR STANDBY comment=NONE
channel d1: backup set complete, elapsed time: 00:06:14
Finished backup at 2011-11-14 21:59:23

released channel: d1

released channel: d2

released channel: d3

released channel: d4

RMAN>
--------------------------------------

3、将备份集传输到备库的/data/oracle/backup/rman目录
scp -r  [email protected]:/u01/rmanbak/for18dg/ /bak/from14/
[root@L-DB-163-18 bak]# scp -r  [email protected]:/u01/rmanbak/for18dg/ /bak/from14/
[email protected]'s password:
standby_MYPORT_20111114_pcmrlqi5_1_1.bak                                                                                                                          100%  341MB  11.4MB/s   00:30
standby_MYPORT_20111114_p9mrlq22_1_1.bak                                                                                                                          100%  190MB  11.2MB/s   00:17
standby_MYPORT_20111114_pamrlq22_1_1.bak                                                                                                                          100%   94MB  11.7MB/s   00:08
standby_MYPORT_20111114_p8mrlq22_1_1.bak                                                                                                                          100%  159MB  11.4MB/s   00:14
standby_MYPORT_20111114_pbmrlqee_1_1.bak                                                                                                                          100%   49MB   9.7MB/s   00:05
standby_MYPORT_20111114_p7mrlq22_1_1.bak                                                                                                                          100%  305MB  11.3MB/s   00:27
standby_MYPORT_20111114_pdmrlqj9_1_1.bak                                                                                                                          100% 1520KB   1.5MB/s   00:00
[root@L-DB-163-18 bak]#

 

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