使用_allow_resetlogs_corruption打开无归档日志rman备份库

使用_allow_resetlogs_corruption打开无归档日志rman备份库

rman还原恢复操作

--还原数据库 RMAN> restore database; --恢复数据库 RMAN> recover database; Starting recover at 2012-03-08 21:20:45 using target database control file instead of recovery catalog allocated channel: ORA_DISK_1 channel ORA_DISK_1: SID=65 device type=DISK starting media recovery RMAN-00571: =========================================================== RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS =============== RMAN-00571: =========================================================== RMAN-03002: failure of recover command at 03/08/2012 21:20:47 RMAN-06053: unable to perform media recovery because of missing log RMAN-06025: no backup of archived log for thread 1 with sequence 2936 and starting SCN of 25991695 found to restore RMAN-06025: no backup of archived log for thread 1 with sequence 2935 and starting SCN of 25991652 found to restore RMAN-06025: no backup of archived log for thread 1 with sequence 2934 and starting SCN of 25991649 found to restore …………………… RMAN-06025: no backup of archived log for thread 1 with sequence 2902 and starting SCN of 25991156 found to restore 这里报日志缺少，实际上是备份的数据库文件后，没有备份归档日志，归档日志全部丢失

进行不完全恢复

SQL> recover database until cancel; ORA-00279: change 25991194 generated at 03/08/2012 20:33:58 needed for thread 1 ORA-00289: suggestion : /opt/oracle/oradata/archivelog/chf/1_2902_752334071.dbf ORA-00280: change 25991194 for thread 1 is in sequence #2902 Specify log: {=suggested | filename | AUTO | CANCEL} cancel 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: '/opt/oracle/oradata/chf/system01.dbf' ORA-01112: media recovery not started SQL> alter database open resetlogs; alter database open resetlogs * ERROR at line 1: ORA-01194: file 1 needs more recovery to be consistent ORA-01110: data file 1: '/opt/oracle/oradata/chf/system01.dbf'

查看相关SCN

SQL> select file#,to_char(checkpoint_change#,'999999999999') from v$datafile; FILE# TO_CHAR(CHECK ---------- ------------- 1 25992214 2 25992214 3 25992214 4 25992214 5 25992214 6 25992214 7 25992214 8 25992214 9 25992214 10 25992214 11 25992214 FILE# TO_CHAR(CHECK ---------- ------------- 13 25992214 14 25992214 13 rows selected. SQL> select file#,online_status,to_char(change#,'999999999999') from v$recover_file; FILE# ONLINE_ TO_CHAR(CHANG ---------- ------- ------------- 1 ONLINE 25991194 2 ONLINE 25991194 3 ONLINE 25991194 4 ONLINE 25991194 5 ONLINE 25991194 6 ONLINE 25991194 7 ONLINE 25991194 8 ONLINE 25991194 9 ONLINE 25991194 10 ONLINE 25991194 11 ONLINE 25991194 FILE# ONLINE_ TO_CHAR(CHANG ---------- ------- ------------- 13 ONLINE 25991194 14 ONLINE 25991194 13 rows selected. SQL> select file#,to_char(checkpoint_change#,'999999999999') from v$datafile_header; FILE# TO_CHAR(CHECK ---------- ------------- 1 25991194 2 25991194 3 25991194 4 25991194 5 25991194 6 25991194 7 25991194 8 25991194 9 25991194 10 25991194 11 25991194 FILE# TO_CHAR(CHECK ---------- ------------- 13 25991194 14 25991194 13 rows selected. --发现数据文件scn和控制文件不一致，重建控制文件，然后查询相关scn SQL> select file#,to_char(checkpoint_change#,'999999999999') from v$datafile; FILE# TO_CHAR(CHECK ---------- ------------- 1 25991194 2 25991194 3 25991194 4 25991194 5 25991194 6 25991194 7 25991194 8 25991194 9 25991194 10 25991194 11 25991194 FILE# TO_CHAR(CHECK ---------- ------------- 13 25991194 14 25991194 13 rows selected. SQL> select file#,online_status,to_char(change#,'999999999999') from v$recover_file; FILE# ONLINE_ TO_CHAR(CHANG ---------- ------- ------------- 1 ONLINE 25991194 2 ONLINE 25991194 3 ONLINE 25991194 4 ONLINE 25991194 5 ONLINE 25991194 6 ONLINE 25991194 7 ONLINE 25991194 8 ONLINE 25991194 9 ONLINE 25991194 10 ONLINE 25991194 11 ONLINE 25991194 FILE# ONLINE_ TO_CHAR(CHANG ---------- ------- ------------- 13 ONLINE 25991194 14 ONLINE 25991194 13 rows selected. SQL> select file#,to_char(checkpoint_change#,'999999999999') from v$datafile_header; FILE# TO_CHAR(CHECK ---------- ------------- 1 25991194 2 25991194 3 25991194 4 25991194 5 25991194 6 25991194 7 25991194 8 25991194 9 25991194 10 25991194 11 25991194 FILE# TO_CHAR(CHECK ---------- ------------- 13 25991194 14 25991194 13 rows selected. --此时所有scn均一致

尝试打开数据库

SQL> alter database open resetlogs; alter database open resetlogs * ERROR at line 1: ORA-01194: file 1 needs more recovery to be consistent ORA-01110: data file 1: '/opt/oracle/oradata/chf/system01.dbf' SQL> recover database using backup controlfile until cancel; ORA-00279: change 25991194 generated at 03/08/2012 20:33:58 needed for thread 1 ORA-00289: suggestion : /opt/oracle/oradata/archivelog/chf/1_2902_752334071.dbf ORA-00280: change 25991194 for thread 1 is in sequence #2902 Specify log: {=suggested | filename | AUTO | CANCEL} cancel 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: '/opt/oracle/oradata/chf/system01.dbf' ORA-01112: media recovery not started SQL> alter database open resetlogs; alter database open resetlogs * ERROR at line 1: ORA-01194: file 1 needs more recovery to be consistent ORA-01110: data file 1: '/opt/oracle/oradata/chf/system01.dbf'

使用隐含参数打开数据库

SQL> create pfile='/tmp/pfile' from spfile; File created. -------/tmp/pfile中加上---------- _allow_resetlogs_corruption= TRUE --------------------------------- SQL> startup mount pfile='/tmp/pfile' force ORACLE instance started. Total System Global Area 622149632 bytes Fixed Size 2230912 bytes Variable Size 419431808 bytes Database Buffers 192937984 bytes Redo Buffers 7548928 bytes Database mounted. SQL> alter database open resetlogs; Database altered. SQL> select open_mode from v$database; OPEN_MODE -------------------- READ WRITE

总结
这次的试验没有多少实际意义，但是可以说明几个问题：
1.所有的数据文件的scn都一致，甚至和控制文件的也一致，数据库不一定可以open成功
(怀疑是数据文件中的scn大于data header scn)
2.对于这样的问题，如果使用bbed修改所有数据文件header的scn不知道是否可以解决
3.如果rman只备份了数据文件而没有任何一个归档日志，数据库通过隐含参数还是可以open，抢救数据