20160331数据文件offline与open resetlogs
[20160331]数据文件offline与open resetlogs.txt
--昨天不小心导致一个数据文件offline，而归档日志已经删除，无法在通过recover恢复到online，通过手工修改online数据文件。
--链接http://blog.itpub.net/267265/viewspace-2071731/
--这让我想起来节前跟别人聊天提到一个恢复操作，数据库无法open，安全起见，通过dg来恢复。设置只读模式，停止日志应用，拷贝文
--件到新机器，建立新的控制文件，打开使用open resetlogs，悲剧发生，有一个数据文件在做恢复时，已经处在offline状态。结果
--resetlog时，没有改变数据文件的RESETLOGS_CHANGE#.提示：
ORA-01190: control file or data file XX is from before the last RESETLOGS
--我当时问出现这种情况如何恢复，我记得对方讲通过提升scn来恢复，我当时觉得很奇怪，提到scn能解决这个问题吗？数据文件里面记
--录RESETLOGS_CHANGE#就能改变吗？当时由于时间关系，这个测试我一直做，今天比较有空做一些测试：
1.环境：
SCOTT@book> @ &r/ver1
PORT_STRING VERSION BANNER
------------------------------ -------------- --------------------------------------------------------------------------------
x86_64/Linux 2.4.xx 11.2.0.4.0 Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
SYS@book> SELECT file#, CHECKPOINT_CHANGE#, CHECKPOINT_TIME,CREATION_CHANGE# , RESETLOGS_CHANGE#,status, CHECKPOINT_COUNT,fuzzy,name,tablespace_name FROM v$datafile_header;
FILE# CHECKPOINT_CHANGE# CHECKPOINT_TIME CREATION_CHANGE# RESETLOGS_CHANGE# STATUS CHECKPOINT_COUNT FUZ NAME TABLESPACE_NAME
----- ------------------ ------------------- ---------------- ----------------- ------- ---------------- --- -------------------------------- ----------------
1 13227498083 2016-03-31 08:34:53 7 13227286650 ONLINE 1000 YES /mnt/ramdisk/book/system01.dbf SYSTEM
2 13227498083 2016-03-31 08:34:53 1834 13227286650 ONLINE 996 YES /mnt/ramdisk/book/sysaux01.dbf SYSAUX
3 13227498083 2016-03-31 08:34:53 923328 13227286650 ONLINE 916 YES /mnt/ramdisk/book/undotbs01.dbf UNDOTBS1
4 13227498083 2016-03-31 08:34:53 16143 13227286650 ONLINE 1000 YES /mnt/ramdisk/book/users01.dbf USERS
5 13227498083 2016-03-31 08:34:53 952916 13227286650 ONLINE 913 YES /mnt/ramdisk/book/example01.dbf EXAMPLE
6 13227498083 2016-03-31 08:34:53 1314508 13227286650 ONLINE 929 YES /mnt/ramdisk/book/sugar01.dbf SUGAR
7 13227498083 2016-03-31 08:34:53 13227207527 13227286650 ONLINE 22 YES /mnt/ramdisk/book/tea01.dbf TEA
7 rows selected.
--每一次open resetlog都会改变RESETLOGS_CHANGE#，我这里当前是13227286650。也可以通过这个视图查询v$database_incarnation ：
SYS@book> select * from v$database_incarnation ;
INCARNATION# RESETLOGS_CHANGE# RESETLOGS_TIME PRIOR_RESETLOGS_CHANGE# PRIOR_RESETLOGS_TIM STATUS RESETLOGS_ID PRIOR_INCARNATION# FLASHBACK_DATABASE_ALLOWED
------------ ----------------- ------------------- ----------------------- ------------------- ------- ------------ ------------------ --------------------------
1 1 2013-08-24 11:37:30 0 PARENT 824297850 0 NO
2 925702 2015-11-24 09:11:12 1 2013-08-24 11:37:30 PARENT 896605872 1 NO
3 13227285139 2016-03-25 16:45:42 925702 2015-11-24 09:11:12 PARENT 907433142 2 NO
4 13227286650 2016-03-25 17:06:01 13227285139 2016-03-25 16:45:42 CURRENT 907434361 3 NO
--我的测试库经历了过几次1->925702->13227285139->13227286650.感觉这个就是当时切换的scn号。注意后面的RESETLOGS_ID跟
--log_archive_format参数的%r有关.
--还可以通过rman的list incarnation;查看
RMAN> list incarnation;
using target database control file instead of recovery catalog
List of Database Incarnations
DB Key Inc Key DB Name DB ID STATUS Reset SCN Reset Time
------- ------- -------- ---------------- --- ---------- ----------
1 1 BOOK 1337401710 PARENT 1 2013-08-24 11:37:30
2 2 BOOK 1337401710 PARENT 925702 2015-11-24 09:11:12
3 3 BOOK 1337401710 PARENT 13227285139 2016-03-25 16:45:42
4 4 BOOK 1337401710 CURRENT 13227286650 2016-03-25 17:06:01
--另外查看参数log_archive_format，里面的%r表示的就是v$database_incarnation的RESETLOGS_ID,这个参数必须包括%r参数。如果你
--open resetlogs的日志的seq又从1开始。
SCOTT@book> show parameter log_archive_format
NAME TYPE VALUE
------------------- ------- ---------------
log_archive_format string %t_%s_%r.dbf
$ ll -l /u01/app/oracle/archivelog/book/
total 19952
-rw-r----- 1 oracle oinstall 20403712 2016-03-31 08:43:00 1_18_907434361.dbf
--这些信息应该保存在控制文件中，如果新建控制文件list incarnation;就看不到了。
--从这里看出如果open resetlogs 前，最好查询视图v$datafile_header确定是否存在表空间或者数据文件offline.
2.测试：
CREATE TABLESPACE TEA DATAFILE
'/mnt/ramdisk/book/tea01.dbf' SIZE 1536K AUTOEXTEND OFF
LOGGING
ONLINE
EXTENT MANAGEMENT LOCAL AUTOALLOCATE
BLOCKSIZE 8K
SEGMENT SPACE MANAGEMENT AUTO
FLASHBACK ON;
SCOTT@book> create table t tablespace tea as select rownum id ,lpad('text',4) name from dual connect by level<=4;
Table created.
SCOTT@book> select rowid,t.* from scott.t ;
ROWID ID NAME
------------------ ---------- --------------------
AAAWgeAAHAAAACLAAA 1 text
AAAWgeAAHAAAACLAAB 2 text
AAAWgeAAHAAAACLAAC 3 text
AAAWgeAAHAAAACLAAD 4 text
SCOTT@book> @ &r/rowid AAAWgeAAHAAAACLAAA
OBJECT FILE BLOCK ROW DBA TEXT
---------- ---------- ---------- ---------- -------------------- ----------------------------------------
92190 7 139 0 7,139 alter system dump datafile 7 block 139 ;
--关机做一个冷备份,便于重复测试.
--session 1:
update t set name='aaaa' where id=1;
commit ;
--session 2:
update t set name='bbbb' where id=2;
--不提交。
--session 3:
SYS@book> alter database datafile 7 offline ;
Database altered.
--session 2:
commit ;
alter system archive log current ;
alter system archive log current ;
alter system archive log current ;
alter system archive log current ;
--切换出全部redo到归档。
SYS@book> shutdown abort ;
ORACLE instance shut down.
3.重新打开数据库看看：
SYS@book> startup mount
ORACLE instance started.
Total System Global Area 634732544 bytes
Fixed Size 2255792 bytes
Variable Size 197133392 bytes
Database Buffers 427819008 bytes
Redo Buffers 7524352 bytes
Database mounted.
SYS@book> SELECT file#, CHECKPOINT_CHANGE#, CHECKPOINT_TIME,CREATION_CHANGE# , RESETLOGS_CHANGE#,status, CHECKPOINT_COUNT,fuzzy,name,tablespace_name FROM v$datafile_header;
FILE# CHECKPOINT_CHANGE# CHECKPOINT_TIME CREATION_CHANGE# RESETLOGS_CHANGE# STATUS CHECKPOINT_COUNT FUZ NAME TABLESPACE_NAME
----- ------------------ ------------------- ---------------- ----------------- ------- ---------------- --- -------------------------------- ----------------
1 13227501337 2016-03-31 09:59:13 7 13227286650 ONLINE 1006 YES /mnt/ramdisk/book/system01.dbf SYSTEM
2 13227501337 2016-03-31 09:59:13 1834 13227286650 ONLINE 1002 YES /mnt/ramdisk/book/sysaux01.dbf SYSAUX
3 13227501337 2016-03-31 09:59:13 923328 13227286650 ONLINE 922 YES /mnt/ramdisk/book/undotbs01.dbf UNDOTBS1
4 13227501337 2016-03-31 09:59:13 16143 13227286650 ONLINE 1006 YES /mnt/ramdisk/book/users01.dbf USERS
5 13227501337 2016-03-31 09:59:13 952916 13227286650 ONLINE 919 YES /mnt/ramdisk/book/example01.dbf EXAMPLE
6 13227501337 2016-03-31 09:59:13 1314508 13227286650 ONLINE 935 YES /mnt/ramdisk/book/sugar01.dbf SUGAR
7 13227500869 2016-03-31 09:53:40 13227207527 13227286650 OFFLINE 26 YES /mnt/ramdisk/book/tea01.dbf TEA
7 rows selected.
--如果我使用 recover database using backup controlfile until cancel;恢复后，不能在使用open打开，必须加入open resetlogs参数。
SYS@book> recover database using backup controlfile until cancel;
ORA-00279: change 13227501224 generated at 03/31/2016 09:10:29 needed for thread 1
ORA-00289: suggestion : /u01/app/oracle/archivelog/book/1_24_907434361.dbf
ORA-00280: change 13227501224 for thread 1 is in sequence #24
Specify log: {<RET>=suggested | filename | AUTO | CANCEL}
auto
ORA-00308: cannot open archived log '/u01/app/oracle/archivelog/book/1_24_907434361.dbf'
ORA-27037: unable to obtain file status
Linux-x86_64 Error: 2: No such file or directory
Additional information: 3
ORA-00308: cannot open archived log '/u01/app/oracle/archivelog/book/1_24_907434361.dbf'
ORA-27037: unable to obtain file status
Linux-x86_64 Error: 2: No such file or directory
Additional information: 3
ORA-01547: warning: RECOVER succeeded but OPEN RESETLOGS would get error below
ORA-01194: file 1 needs more recovery to be consistent
ORA-01110: data file 1: '/mnt/ramdisk/book/system01.dbf'
SYS@book> @ &r/logfile
GROUP# THREAD# SEQUENCE# BYTES BLOCKSIZE MEMBERS ARC STATUS FIRST_CHANGE# FIRST_TIME NEXT_CHANGE# NEXT_TIME GROUP# STATUS TYPE MEMBER IS_
------ ------- --------- ----------- --------- ------- --- ---------- ------------- ------------------- ------------ ------------------- ------ ---------- ---------- -------------------------------------------------- ---
1 1 22 52428800 512 1 YES INACTIVE 13227501329 2016-03-31 09:59:09 13227501333 2016-03-31 09:59:12 1 ONLINE /mnt/ramdisk/book/redo01.log NO
2 1 23 52428800 512 1 YES INACTIVE 13227501333 2016-03-31 09:59:12 13227501337 2016-03-31 09:59:13 2 ONLINE /mnt/ramdisk/book/redo02.log NO
3 1 24 52428800 512 1 NO CURRENT 13227501337 2016-03-31 09:59:13 2.814750E+14 3 ONLINE /mnt/ramdisk/book/redo03.log NO
--还需要 /mnt/ramdisk/book/redo03.log.
SYS@book> SELECT file#, CHECKPOINT_CHANGE#, CHECKPOINT_TIME,CREATION_CHANGE# , RESETLOGS_CHANGE#,status, CHECKPOINT_COUNT,fuzzy,name,tablespace_name FROM v$datafile_header where file# in (1,7);
FILE# CHECKPOINT_CHANGE# CHECKPOINT_TIME CREATION_CHANGE# RESETLOGS_CHANGE# STATUS CHECKPOINT_COUNT FUZ NAME TABLESPACE_NAME
----- ------------------ ------------------- ---------------- ----------------- ---------- ---------------- --- -------------------------------------------------- ------------------------------
1 13227501337 2016-03-31 09:59:13 7 13227286650 ONLINE 1006 YES /mnt/ramdisk/book/system01.dbf SYSTEM
7 13227500869 2016-03-31 09:53:40 13227207527 13227286650 ONLINE 26 YES /mnt/ramdisk/book/tea01.dbf TEA
--另外可以发现数据文件7在recover时已经设置为online.
SYS@book> recover database using backup controlfile until cancel;
ORA-00279: change 13227500869 generated at 03/31/2016 09:53:40 needed for thread 1
ORA-00289: suggestion : /u01/app/oracle/archivelog/book/1_20_907434361.dbf
ORA-00280: change 13227500869 for thread 1 is in sequence #20
Specify log: {<RET>=suggested | filename | AUTO | CANCEL}
auto
ORA-00279: change 13227501325 generated at 03/31/2016 09:59:08 needed for thread 1
ORA-00289: suggestion : /u01/app/oracle/archivelog/book/1_21_907434361.dbf
ORA-00280: change 13227501325 for thread 1 is in sequence #21
ORA-00278: log file '/u01/app/oracle/archivelog/book/1_20_907434361.dbf' no longer needed for this recovery
ORA-00279: change 13227501329 generated at 03/31/2016 09:59:09 needed for thread 1
ORA-00289: suggestion : /u01/app/oracle/archivelog/book/1_22_907434361.dbf
ORA-00280: change 13227501329 for thread 1 is in sequence #22
ORA-00278: log file '/u01/app/oracle/archivelog/book/1_21_907434361.dbf' no longer needed for this recovery
ORA-00279: change 13227501333 generated at 03/31/2016 09:59:12 needed for thread 1
ORA-00289: suggestion : /u01/app/oracle/archivelog/book/1_23_907434361.dbf
ORA-00280: change 13227501333 for thread 1 is in sequence #23
ORA-00278: log file '/u01/app/oracle/archivelog/book/1_22_907434361.dbf' no longer needed for this recovery
ORA-00279: change 13227501337 generated at 03/31/2016 09:59:13 needed for thread 1
ORA-00289: suggestion : /u01/app/oracle/archivelog/book/1_24_907434361.dbf
ORA-00280: change 13227501337 for thread 1 is in sequence #24
ORA-00278: log file '/u01/app/oracle/archivelog/book/1_23_907434361.dbf' no longer needed for this recovery
ORA-00308: cannot open archived log '/u01/app/oracle/archivelog/book/1_24_907434361.dbf'
ORA-27037: unable to obtain file status
Linux-x86_64 Error: 2: No such file or directory
Additional information: 3
ORA-01547: warning: RECOVER succeeded but OPEN RESETLOGS would get error below
ORA-01194: file 1 needs more recovery to be consistent
ORA-01110: data file 1: '/mnt/ramdisk/book/system01.dbf'
--我觉得这个地方是执行恢复数据文件7.因为前面提示是差seq=24.继续恢复:
SYS@book> recover database using backup controlfile until cancel;
ORA-00279: change 13227501337 generated at 03/31/2016 09:59:13 needed for thread 1
ORA-00289: suggestion : /u01/app/oracle/archivelog/book/1_24_907434361.dbf
ORA-00280: change 13227501337 for thread 1 is in sequence #24
Specify log: {<RET>=suggested | filename | AUTO | CANCEL}
/mnt/ramdisk/book/redo03.log
Log applied.
Media recovery complete.
SYS@book> SELECT file#, CHECKPOINT_CHANGE#, CHECKPOINT_TIME,CREATION_CHANGE# , RESETLOGS_CHANGE#,status, CHECKPOINT_COUNT,fuzzy,name,tablespace_name FROM v$datafile_header where file# in (1,7);
FILE# CHECKPOINT_CHANGE# CHECKPOINT_TIME CREATION_CHANGE# RESETLOGS_CHANGE# STATUS CHECKPOINT_COUNT FUZ NAME TABLESPACE_NAME
----- ------------------ ------------------- ---------------- ----------------- ---------- ---------------- --- -------------------------------------------------- ------------------------------
1 13227501343 2016-03-31 09:59:24 7 13227286650 ONLINE 1007 NO /mnt/ramdisk/book/system01.dbf SYSTEM
7 13227501343 2016-03-31 09:59:24 13227207527 13227286650 ONLINE 27 NO /mnt/ramdisk/book/tea01.dbf TEA
SYS@book> alter database datafile 7 offline ;
Database altered.
SYS@book> SELECT file#, CHECKPOINT_CHANGE#, CHECKPOINT_TIME,CREATION_CHANGE# , RESETLOGS_CHANGE#,status, CHECKPOINT_COUNT,fuzzy,name,tablespace_name FROM v$datafile_header where file# in (1,7);
FILE# CHECKPOINT_CHANGE# CHECKPOINT_TIME CREATION_CHANGE# RESETLOGS_CHANGE# STATUS CHECKPOINT_COUNT FUZ NAME TABLESPACE_NAME
----- ------------------ ------------------- ---------------- ----------------- ---------- ---------------- --- -------------------------------------------------- ------------------------------
1 13227501343 2016-03-31 09:59:24 7 13227286650 ONLINE 1007 NO /mnt/ramdisk/book/system01.dbf SYSTEM
7 13227501343 2016-03-31 09:59:24 13227207527 13227286650 OFFLINE 27 NO /mnt/ramdisk/book/tea01.dbf TEA
-- 数据文件7已经offline.
SYS@book> alter database read ;
alter database read
*
ERROR at line 1:
ORA-02231: missing or invalid option to ALTER DATABASE
SYS@book> alter database open resetlogs;
Database altered.
SYS@book> SELECT file#, CHECKPOINT_CHANGE#, CHECKPOINT_TIME,CREATION_CHANGE# , RESETLOGS_CHANGE#,status, CHECKPOINT_COUNT,fuzzy,name,tablespace_name FROM v$datafile_header where file# in (1,7);
FILE# CHECKPOINT_CHANGE# CHECKPOINT_TIME CREATION_CHANGE# RESETLOGS_CHANGE# STATUS CHECKPOINT_COUNT FUZ NAME TABLESPACE_NAME
----- ------------------ ------------------- ---------------- ----------------- ---------- ---------------- --- -------------------------------------------------- ------------------------------
1 13227501347 2016-03-31 10:08:00 7 13227501344 ONLINE 1009 YES /mnt/ramdisk/book/system01.dbf SYSTEM
7 13227501343 2016-03-31 09:59:24 13227207527 13227286650 OFFLINE 27 NO /mnt/ramdisk/book/tea01.dbf TEA
--数据文件7的RESETLOGS_CHANGE#与数据文件1的RESETLOGS_CHANGE#不一致.
SYS@book> alter database datafile 7 online ;
alter database datafile 7 online
*
ERROR at line 1:
ORA-01190: control file or data file 7 is from before the last RESETLOGS
ORA-01110: data file 7: '/mnt/ramdisk/book/tea01.dbf'
--不要被ORA-01190提示蒙骗,实际上10g以后可以跨resetlogs恢复,只要归档日志全部都在.
RMAN> list incarnation;
using target database control file instead of recovery catalog
List of Database Incarnations
DB Key Inc Key DB Name DB ID STATUS Reset SCN Reset Time
------- ------- -------- ---------------- --- ---------- ----------
1 1 BOOK 1337401710 PARENT 1 2013-08-24 11:37:30
2 2 BOOK 1337401710 PARENT 925702 2015-11-24 09:11:12
3 3 BOOK 1337401710 PARENT 13227285139 2016-03-25 16:45:42
4 4 BOOK 1337401710 PARENT 13227286650 2016-03-25 17:06:01
5 5 BOOK 1337401710 CURRENT 13227501344 2016-03-31 10:07:59
SYS@book> recover datafile 7;
Media recovery complete.
SYS@book> alter database datafile 7 online ;
Database altered.
SYS@book> select rowid,t.* from scott.t ;
ROWID ID NAME
------------------ ------------ ---------
AAAWgeAAHAAAACLAAA 1 aaaa
AAAWgeAAHAAAACLAAB 2 bbbb
AAAWgeAAHAAAACLAAC 3 text
AAAWgeAAHAAAACLAAD 4 text
--没有任何丢失.
SYS@book> SELECT file#, CHECKPOINT_CHANGE#, CHECKPOINT_TIME,CREATION_CHANGE# , RESETLOGS_CHANGE#,status, CHECKPOINT_COUNT,fuzzy,name,tablespace_name FROM v$datafile_header;
FILE# CHECKPOINT_CHANGE# CHECKPOINT_TIME CREATION_CHANGE# RESETLOGS_CHANGE# STATUS CHECKPOINT_COUNT FUZ NAME TABLESPACE_NAME
----- ------------------ ------------------- ---------------- ----------------- ---------- ---------------- --- -------------------------------------------------- ------------------------------
1 13227501347 2016-03-31 10:08:00 7 13227501344 ONLINE 1009 YES /mnt/ramdisk/book/system01.dbf SYSTEM
2 13227501347 2016-03-31 10:08:00 1834 13227501344 ONLINE 1005 YES /mnt/ramdisk/book/sysaux01.dbf SYSAUX
3 13227501347 2016-03-31 10:08:00 923328 13227501344 ONLINE 925 YES /mnt/ramdisk/book/undotbs01.dbf UNDOTBS1
4 13227501347 2016-03-31 10:08:00 16143 13227501344 ONLINE 1009 YES /mnt/ramdisk/book/users01.dbf USERS
5 13227501347 2016-03-31 10:08:00 952916 13227501344 ONLINE 922 YES /mnt/ramdisk/book/example01.dbf EXAMPLE
6 13227501347 2016-03-31 10:08:00 1314508 13227501344 ONLINE 938 YES /mnt/ramdisk/book/sugar01.dbf SUGAR
7 13227501818 2016-03-31 10:12:53 13227207527 13227501344 ONLINE 29 YES /mnt/ramdisk/book/tea01.dbf TEA
7 rows selected.
--注意一个细节,我的recover database using backup controlfile until cancel;数据文件7已经恢复到CHECKPOINT_CHANGE#=13227501343,而open resetlogs的scn=13227501344,仅仅相差1.
--如果存在一定差距,能恢复吗? 看一篇帖子.
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