select * from v$log;
select * from v$logfile;
9
17
ONLINE
+DATA/txkhzs/onlinelog/group_17.2134.910290337
NO
10
18
ONLINE
+DATA/txkhzs/onlinelog/group_18.2135.910290339
NO
11
19
ONLINE
+DATA/txkhzs/onlinelog/group_19.2137.910290339
NO
12
20
ONLINE
+DATA/txkhzs/onlinelog/group_20.2138.910290341
NO
13
21
ONLINE
+DATA/txkhzs/onlinelog/group_21.2141.910290341
NO
14
22
ONLINE
+DATA/txkhzs/onlinelog/group_22.2139.910290341
NO
15
23
ONLINE
+DATA/txkhzs/onlinelog/group_23.2142.910290343
NO
16
24
ONLINE
+DATA/txkhzs/onlinelog/group_24.2145.910290343
NO
group_21.2141.910290341 ---group#+文件号+随机数
来dump 下集群环境下的redo logfile
SQL> oradebug setmypid
Statement processed.
SQL> alter system dump logfile '+FASTDATA/emdw/onlinelog/group_6.286.952955435';
alter session set tracefile_identifier='02.trc';
SQL> alter system dump logfile '+FASTDATA/emdw/onlinelog/group_6.286.952955435';
oradebug tracefile_name
REDO RECORD - Thread:1 RBA: 0x000122.00000002.0010 LEN: 0x0070 VLD: 0x06
SCN: 0x0000.006efdec SUBSCN: 1 11/14/2018 20:57:30
(LWN RBA: 0x000122.00000002.0010 LEN: 0003 NST: 0001 SCN: 0x0000.006efdec)
CHANGE #1 MEDIA RECOVERY MARKER SCN:0x0000.00000000 SEQ:0 OP:23.1 ENC:0
Block Written - afn: 2 rdba: 0x0080fcb8 BFT:(1024,8453304) non-BFT:(2,64696)
scn: 0x0000.006efd34 seq: 0x01 flg:0x06
REDO RECORD - Thread:1 RBA: 0x000122.00000002.0080 LEN: 0x0044 VLD: 0x02
SCN: 0x0000.006efdec SUBSCN: 1 11/14/2018 20:57:30
CHANGE #1 MEDIA RECOVERY MARKER SCN:0x0000.00000000 SEQ:0 OP:23.1 ENC:0
Block Written - afn: 6 rdba: 0x018010ef BFT:(1024,25170159) non-BFT:(6,4335)
scn: 0x0000.006efd49 seq: 0x03 flg:0x04
通过10013跟踪oracle启动
startup mount
oradebug setmypid
alter session set events '10013 trace name context forever,level 1';
alter database open;
oradebug close_trace
SQL> oradebug tracefile_name
/u01/app/oracle/diag/rdbms/orcl/orcl/trace/orcl_ora_29940.trc
-----session1
SQL> delete from test;
1 row deleted.
-------session2
SQL> shutdown abort;
ORACLE instance shut down.
-----session3
SQL> startup mount;
ORACLE instance started.
Total System Global Area 313159680 bytes
Fixed Size 2252824 bytes
Variable Size 188747752 bytes
Database Buffers 117440512 bytes
Redo Buffers 4718592 bytes
Database mounted.
SQL> oradebug setmypid
Statement processed.
SQL> alter session set events '10013 trace name context forever,level 1';
Session altered.
SQL> alter database open;
Database altered.
SQL> oradebug close_trace
Statement processed.
SQL> oradebug tracefile_name
/u01/app/oracle/diag/rdbms/orcl/orcl/trace/orcl_ora_30111.trc
---------alert日志+++++++++
Beginning crash recovery of 1 threads -----------应用线程1的redo
parallel recovery started with 7 processes
Started redo scan
Completed redo scan
read 39 KB redo, 34 data blocks need recovery
Started redo application at
Thread 1: logseq 292, block 64390
Recovery of Online Redo Log: Thread 1 Group 1 Seq 292 Reading mem 0
Mem# 0: /u01/app/oracle/oradata/orcl/redo01.log
Completed redo application of 0.01MB
Completed crash recovery at
Thread 1: logseq 292, block 64469, scn 7349812 --------redo恢复完成
34 data blocks read, 34 data blocks written, 39 redo k-bytes read
Thu Nov 15 13:51:27 2018
LGWR: STARTING ARCH PROCESSES
查看 trace文件内容
Thread 1 checkpoint: logseq 292, block 63694, scn 7329171
cache-low rba: logseq 292, block 64390 ---- low rba 实例恢复的起点
on-disk rba: logseq 292, block 64469, scn 7329812 ---- on disk rba
start recovery at logseq 292, block 64390, scn 0 -- low rba的地址，实例恢复的起点
