年归档：2022

PostgreSQL恢复系列:pg_filedump基本使用

发表于 2022 年 6 月 3 日由惜分飞

当PostgreSQL遇到重大故障,使用各种方法都无法直接启动数据库，可以考虑使用类似oracle dul工具,直接离线方式读取文件进行恢复.这个工具为pg_filedump
pg_filedump安装

[root@xifenfei ~]# yum install pg_filedump_14.x86_64
Loaded plugins: langpacks, ulninfo
Resolving Dependencies
--> Running transaction check
---> Package pg_filedump_14.x86_64 0:14.1-1.rhel7 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

======================================================================================================================
 Package                            Arch      Version                 Repository                                 Size
======================================================================================================================
Installing:                                 
 pg_filedump_14                     x86_64    14.1-1.rhel7            pgdg14                                     43 k
                                            
Transaction Summary                         
======================================================================================================================
Install  1 Package

Total download size: 43 k
Installed size: 81 k
Is this ok [y/d/N]: y
Downloading packages:
pg_filedump_14-14.1-1.rhel7.x86_64.rpm                                              |  43 kB  00:00:02     
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Installing : pg_filedump_14-14.1-1.rhel7.x86_64                                                      1/1 
  Verifying  : pg_filedump_14-14.1-1.rhel7.x86_64                                                      1/1 

Installed:
  pg_filedump_14.x86_64 0:14.1-1.rhel7                                                                     

Complete!
-bash-4.2$ pg_filedump 

Version 14.1 (for PostgreSQL 8.x .. 14.x)
Copyright (c) 2002-2010 Red Hat, Inc.
Copyright (c) 2011-2022, PostgreSQL Global Development Group

Usage: pg_filedump [-abcdfhikxy] [-R startblock [endblock]] [-D attrlist] [-S blocksize] [-s segsize] [-n segnumber] file

Display formatted contents of a PostgreSQL heap/index/control file
Defaults are: relative addressing, range of the entire file, block
               size as listed on block 0 in the file

The following options are valid for heap and index files:
  -a  Display absolute addresses when formatting (Block header
      information is always block relative)
  -b  Display binary block images within a range (Option will turn
      off all formatting options)
  -d  Display formatted block content dump (Option will turn off
      all other formatting options)
  -D  Decode tuples using given comma separated list of types
      Supported types:
        bigint bigserial bool char charN date float float4 float8 int
        json macaddr name numeric oid real serial smallint smallserial text
        time timestamp timestamptz timetz uuid varchar varcharN xid xml
      ~ ignores all attributes left in a tuple
  -f  Display formatted block content dump along with interpretation
  -h  Display this information
  -i  Display interpreted item details
  -k  Verify block checksums
  -o  Do not dump old values.
  -R  Display specific block ranges within the file (Blocks are
      indexed from 0)
        [startblock]: block to start at
        [endblock]: block to end at
      A startblock without an endblock will format the single block
  -s  Force segment size to [segsize]
  -t  Dump TOAST files
  -v  Ouput additional information about TOAST relations
  -n  Force segment number to [segnumber]
  -S  Force block size to [blocksize]
  -x  Force interpreted formatting of block items as index items
  -y  Force interpreted formatting of block items as heap items

The following options are valid for control files:
  -c  Interpret the file listed as a control file
  -f  Display formatted content dump along with interpretation
  -S  Force block size to [blocksize]
Additional functions:
  -m  Interpret file as pg_filenode.map file and print contents (all
      other options will be ignored)

Report bugs to <pgsql-bugs@postgresql.org>

创建测试表

-bash-4.2$ psql
psql (14.3)
Type "help" for help.

postgres=# create table pg_xifenfei(id int,name varchar(100));
CREATE TABLE
postgres=# insert into pg_xifenfei values(1,'www.xifenfei.com');
INSERT 0 1
postgres=# insert into pg_xifenfei values(2,'xienfei_pg_recovery');
INSERT 0 1
postgres=# select * from pg_xifenfei;
 id |        name         
----+---------------------
  1 | www.xifenfei.com
  2 | xienfei_pg_recovery
(2 rows)

postgres=#

pg_filedump恢复数据

-bash-4.2$ pg_filedump /var/lib/pgsql/14/data/base/14487/16384

*******************************************************************
* PostgreSQL File/Block Formatted Dump Utility
*
* File: /var/lib/pgsql/14/data/base/14487/16384
* Options used: None
*******************************************************************

Block    0 ********************************************************
<Header> -----
 Block Offset: 0x00000000         Offsets: Lower      32 (0x0020)
 Block: Size 8192  Version    4            Upper    8096 (0x1fa0)
 LSN:  logid      0 recoff 0x16299cf0      Special  8192 (0x2000)
 Items:    2                      Free Space: 8064
 Checksum: 0x0000  Prune XID: 0x00000000  Flags: 0x0000 ()
 Length (including item array): 32

<Data> -----
 Item   1 -- Length:   45  Offset: 8144 (0x1fd0)  Flags: NORMAL
 Item   2 -- Length:   48  Offset: 8096 (0x1fa0)  Flags: NORMAL


*** End of File Encountered. Last Block Read: 0 ***

-bash-4.2$ pg_filedump -D int,charn /var/lib/pgsql/14/data/base/14487/16384|grep COPY
COPY: 1 www.xifenfei.com
COPY: 2 xienfei_pg_recovery
-bash-4.2$ pg_filedump -D int,charn /var/lib/pgsql/14/data/base/14487/16384|grep COPY
> |awk '{$1=null;print $0}'>/tmp/pg_xifenfei_rec
-bash-4.2$ sed -i 's/^[ ]*//g' /tmp/pg_xifenfei_rec

导入数据验证

postgres=# truncate table pg_xifenfei;
TRUNCATE TABLE
postgres=# select * from pg_xifenfei;
 id | name 
----+------
(0 rows)
postgres=# copy pg_xifenfei from '/tmp/pg_xifenfei_rec'(DELIMITER ' ');
COPY 2
postgres=# select * from pg_xifenfei;
 id |        name         
----+---------------------
  1 | www.xifenfei.com
  2 | xienfei_pg_recovery
(2 rows)

通过上述简单测试证明,在PG数据库出现极端情况下，可以使用该方法进行最后的数据恢复,减少因为数据丢失带来的损失.

发表在 PostgreSQL恢复 | 标签为 pg_filedump, pg恢复, pg文件恢复 | 评论关闭

Oracle断电故障处理

发表于 2022 年 5 月 31 日由惜分飞

异常断电导致数据库异常恢复文件报ORA-00283 ORA-00742 ORA-00312

 
D:\check_db>sqlplus / as sysdba

SQL*Plus: Release 11.2.0.4.0 Production on 星期二 5月 31 00:38:42 2022

Copyright (c) 1982, 2013, Oracle.  All rights reserved.


连接到:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> recover datafile 1;
ORA-00283: 恢复会话因错误而取消
ORA-00742: 日志读取在线程 %d 序列 %d 块 %d 中检测到写入丢失情况
ORA-00312: 联机日志 3 线程 1:
'D:\APP\ADMINISTRATOR\FAST_RECOVERY_AREA\ORCL\ONLINELOG\O1_MF_3_HJ32KJD5_.LOG'

这个错误比较明显是由于异常断电引起的写丢失导致.而且这种故障在没有备份的情况下，没有什么好处理方法,只能屏蔽一致性强制拉库,尝试强制拉库报错如下

SQL> startup mount pfile='d:/pfile.txt'
ORACLE 例程已经启动。

Total System Global Area 2.0310E+10 bytes
Fixed Size                  2290000 bytes
Variable Size            3690991280 bytes
Database Buffers         1.6576E+10 bytes
Redo Buffers               40837120 bytes
数据库装载完毕。
SQL> recover database until cancel;
ORA-00279: 更改 18755939194213 (在  生成) 对于线程 1 是必需的


指定日志: {<RET>=suggested | filename | AUTO | CANCEL}
D:\APP\ADMINISTRATOR\FAST_RECOVERY_AREA\ORCL\ONLINELOG\O1_MF_3_HJ32KJD5_.LOG
ORA-00600: internal error code, arguments: [3020], [2], [78824], [8467432], [],
[], [], [], [], [], [], []
ORA-10567: Redo is inconsistent with data block (file# 2, block# 78824, file
offset is 645726208 bytes)
ORA-10564: tablespace SYSAUX
ORA-01110: data file 2: 'D:\ORADATA\ORCL\SYSAUX01.DBF'
ORA-10561: block type 'TRANSACTION MANAGED INDEX BLOCK', data object# 80834


ORA-01112: 未启动介质恢复


SQL> alter database open resetlogs;
alter database open resetlogs
*
第 1 行出现错误:
ORA-00600: 内部错误代码, 参数: [krsi_al_hdr_update.15], [4294967295], [], [],[], [], [], [], [], [], [], []

ORA-600 krsi_al_hdr_update.15错误,主要是由于redo异常导致无法resetlogs成功,具体参考：Alter Database Open Resetlogs returns error ORA-00600: [krsi_al_hdr_update.15], (Doc ID 2026541.1)描述,处理这个问题之后,再次resetlogs库，报ORA-600 2662错误

SQL> alter database open resetlogs;
alter database open resetlogs
*
第 1 行出现错误:
ORA-00603: ORACLE server session terminated by fatal error
ORA-00600: internal error code, arguments: [2662], [4366], [4112122046],
[4366], [4112228996], [12583040], [], [], [], [], [], []
ORA-00600: internal error code, arguments: [2662], [4366], [4112122045],
[4366], [4112228996], [12583040], [], [], [], [], [], []
ORA-01092: ORACLE instance terminated. Disconnection forced
ORA-00600: internal error code, arguments: [2662], [4366], [4112122040],
[4366], [4112228996], [12583040], [], [], [], [], [], []
进程 ID: 4644
会话 ID: 1701 序列号: 3

这个问题比较简单,通过修改scn即可绕过去,之后数据库open报ORA-600 4194等错误

SQL> alter database open ;
alter database open 
*
第 1 行出现错误:
ORA-00600: 内部错误代码, 参数: [4194], [

SMON: enabling tx recovery
Database Characterset is ZHS16GBK
Errors in file D:\APP\ADMINISTRATOR\diag\rdbms\orcl\orcl\trace\orcl_smon_5112.trc  (incident=322982):
ORA-00600: internal error code, arguments: [4137], [10.33.3070116], [0], [0], [], [], [], [], [], [], [], []
Incident details in: D:\APP\ADMINISTRATOR\diag\rdbms\orcl\orcl\incident\incdir_322982\orcl_smon_5112_i322982.trc
Use ADRCI or Support Workbench to package the incident.
See Note 411.1 at My Oracle Support for error and packaging details.
ARC3: Archival started
ARC0: STARTING ARCH PROCESSES COMPLETE
replication_dependency_tracking turned off (no async multimaster replication found)
LOGSTDBY: Validating controlfile with logical metadata
LOGSTDBY: Validation complete
Errors in file D:\APP\ADMINISTRATOR\diag\rdbms\orcl\orcl\trace\orcl_ora_3340.trc  (incident=323030):
ORA-00600: 内部错误代码, 参数: [4194], [
Incident details in: D:\APP\ADMINISTRATOR\diag\rdbms\orcl\orcl\incident\incdir_323030\orcl_ora_3340_i323030.trc
Use ADRCI or Support Workbench to package the incident.
See Note 411.1 at My Oracle Support for error and packaging details.
Tue May 31 09:05:04 2022
Sweep [inc][322982]: completed
ORACLE Instance orcl (pid = 13) - Error 600 encountered while recovering transaction (10, 33).
Errors in file D:\APP\ADMINISTRATOR\diag\rdbms\orcl\orcl\trace\orcl_smon_5112.trc:
ORA-00600: internal error code, arguments: [4137], [10.33.3070116], [0], [0], [], [], [], [], [], [], [], []
Checker run found 1 new persistent data failures
Tue May 31 09:05:05 2022
Sweep [inc][323030]: completed
Sweep [inc2][322982]: completed
Tue May 31 09:05:14 2022
Errors in file D:\APP\ADMINISTRATOR\diag\rdbms\orcl\orcl\trace\orcl_smon_5112.trc  (incident=322983):
ORA-00600: internal error code, arguments: [4193], [10.33.3070116], [0], [], [], [], [], [], [], [], [], []
Incident details in: D:\APP\ADMINISTRATOR\diag\rdbms\orcl\orcl\incident\incdir_322983\orcl_smon_5112_i322983.trc
Use ADRCI or Support Workbench to package the incident.
See Note 411.1 at My Oracle Support for error and packaging details.
Tue May 31 09:05:14 2022
ORA-600 signalled during: alter database open...
Block recovery stopped at EOT rba 2.61.16
Block recovery completed at rba 2.61.16, scn 4366.4112429058
Block recovery from logseq 2, block 60 to scn 18755939643393
Recovery of Online Redo Log: Thread 1 Group 2 Seq 2 Reading mem 0
  Mem# 0: D:\APP\ADMINISTRATOR\FAST_RECOVERY_AREA\ORCL\ONLINELOG\O1_MF_2_K9BSVC11_.LOG
Block recovery completed at rba 2.61.16, scn 4366.4112429058
Dumping diagnostic data in directory=[cdmp_2022053],requested by(instance=1,osid=5112(SMON)),summary=[incident=322983].
Errors in file D:\APP\ADMINISTRATOR\diag\rdbms\orcl\orcl\trace\orcl_smon_5112.trc:
ORA-01595: error freeing extent (3) of rollback segment (1))
ORA-00600: internal error code, arguments: [4193], [10.33.3070116], [3], [], [], [], [], [], [], [], [], []

对异常undo进行处理,数据库正常open成功

SQL> shutdown immediate;
ORA-00600: 内部错误代码, 参数: [4193], [


SQL> shutdown abort;
ORACLE 例程已经关闭。
SQL> startup mount
ORACLE 例程已经启动。

Total System Global Area 2.0310E+10 bytes
Fixed Size                  2290000 bytes
Variable Size            3690991280 bytes
Database Buffers         1.6576E+10 bytes
Redo Buffers               40837120 bytes
数据库装载完毕。
SQL> alter database open;

数据库已更改。

hcheck检测有一些字典不一致,建议客户逻辑导出,然后导入到新库中

HCheck Version 07MAY18 on 31-5月 -2022 09:12:22
----------------------------------------------
Catalog Version 11.2.0.4.0 (1102000400)
db_name: ORCL

                                   Catalog       Fixed
Procedure Name                     Version    Vs Release    Timestamp      Resul
t
------------------------------ ... ---------- -- ---------- -------------- -----
-
.- LobNotInObj                 ... 1102000400 <=  *All Rel* 05/31 09:12:22 PASS
.- MissingOIDOnObjCol          ... 1102000400 <=  *All Rel* 05/31 09:12:22 PASS
.- SourceNotInObj              ... 1102000400 <=  *All Rel* 05/31 09:12:22 PASS
.- OversizedFiles              ... 1102000400 <=  *All Rel* 05/31 09:12:22 PASS
.- PoorDefaultStorage          ... 1102000400 <=  *All Rel* 05/31 09:12:22 PASS
.- PoorStorage                 ... 1102000400 <=  *All Rel* 05/31 09:12:22 PASS
.- TabPartCountMismatch        ... 1102000400 <=  *All Rel* 05/31 09:12:22 PASS
.- OrphanedTabComPart          ... 1102000400 <=  *All Rel* 05/31 09:12:22 PASS
.- MissingSum$                 ... 1102000400 <=  *All Rel* 05/31 09:12:22 PASS
.- MissingDir$                 ... 1102000400 <=  *All Rel* 05/31 09:12:22 PASS
.- DuplicateDataobj            ... 1102000400 <=  *All Rel* 05/31 09:12:22 PASS
.- ObjSynMissing               ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- ObjSeqMissing               ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- OrphanedUndo                ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- OrphanedIndex               ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- OrphanedIndexPartition      ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- OrphanedIndexSubPartition   ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- OrphanedTable               ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- OrphanedTablePartition      ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- OrphanedTableSubPartition   ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- MissingPartCol              ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- OrphanedSeg$                ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- OrphanedIndPartObj#         ... 1102000400 <=  *All Rel* 05/31 09:12:23 FAIL

HCKE-0024: Orphaned Index Partition Obj# (no OBJ$) (Doc ID 1360935.1)
ORPHAN INDPART$: OBJ#=149167 BO#=6378 - no OBJ$ row
ORPHAN INDPART$: OBJ#=149168 BO#=6378 - no OBJ$ row

.- DuplicateBlockUse           ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- FetUet                      ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- Uet0Check                   ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- SeglessUET                  ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- BadInd$                     ... 1102000400 <=  *All Rel* 05/31 09:12:23 FAIL

HCKE-0030: OBJ$ INDEX entry has no IND$ or INDPART$/INDSUBPART$ entry (Doc ID 13
60528.1)
OBJ$ INDEX PARTITION has no INDPART$ entry: Obj#=148278 SYS Name=WRH$_FILESTATXS
_PK PARTITION=WRH$_FILEST_1572571104_16462
OBJ$ INDEX PARTITION has no INDPART$ entry: Obj#=148920 SYS Name=WRH$_FILESTATXS
_PK PARTITION=WRH$_FILEST_1572571104_16678

.- BadTab$                     ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- BadIcolDepCnt               ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- ObjIndDobj                  ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- TrgAfterUpgrade             ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- ObjType0                    ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- BadOwner                    ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- StmtAuditOnCommit           ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- BadPublicObjects            ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- BadSegFreelist              ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- BadDepends                  ... 1102000400 <=  *All Rel* 05/31 09:12:23 WARN

HCKW-0016: Dependency$ p_timestamp mismatch for VALID objects (Doc ID 1361045.1)

[E] - P_OBJ#=6376 D_OBJ#=6765

.- CheckDual                   ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- ObjectNames                 ... 1102000400 <=  *All Rel* 05/31 09:12:23 PASS
.- BadCboHiLo                  ... 1102000400 <=  *All Rel* 05/31 09:12:24 PASS
.- ChkIotTs                    ... 1102000400 <=  *All Rel* 05/31 09:12:24 PASS
.- NoSegmentIndex              ... 1102000400 <=  *All Rel* 05/31 09:12:24 PASS
.- BadNextObject               ... 1102000400 <=  *All Rel* 05/31 09:12:24 PASS
.- DroppedROTS                 ... 1102000400 <=  *All Rel* 05/31 09:12:24 PASS
.- FilBlkZero                  ... 1102000400 <=  *All Rel* 05/31 09:12:24 PASS
.- DbmsSchemaCopy              ... 1102000400 <=  *All Rel* 05/31 09:12:24 PASS
.- OrphanedObjError            ... 1102000400 >  1102000000 05/31 09:12:24 PASS
.- ObjNotLob                   ... 1102000400 <=  *All Rel* 05/31 09:12:24 PASS
.- MaxControlfSeq              ... 1102000400 <=  *All Rel* 05/31 09:12:24 PASS
.- SegNotInDeferredStg         ... 1102000400 >  1102000000 05/31 09:12:24 PASS
.- SystemNotRfile1             ... 1102000400 >   902000000 05/31 09:12:24 PASS
.- DictOwnNonDefaultSYSTEM     ... 1102000400 <=  *All Rel* 05/31 09:12:24 PASS
.- OrphanTrigger               ... 1102000400 <=  *All Rel* 05/31 09:12:24 PASS
.- ObjNotTrigger               ... 1102000400 <=  *All Rel* 05/31 09:12:24 PASS
---------------------------------------
31-5月 -2022 09:12:24  Elapsed: 2 secs
---------------------------------------
Found 4 potential problem(s) and 1 warning(s)
Contact Oracle Support with the output and trace file
to check if the above needs attention or not

PL/SQL 过程已成功完成。

发表在 Oracle备份恢复 | 标签为 krsi_al_hdr_update.15, ORA-00742, ORA-600 2662, ORA-600 4194, oracle异常恢复, oracle断电恢复 | 评论关闭

PostgreSQL恢复系列:pg_control异常恢复

发表于 2022 年 5 月 30 日由惜分飞

在PG中pg_control文件类似oracle数据库的control文件(控制文件),在Oracle中如果该文件丢失/损坏,可以通过alter database create controlfile命令进行创建,对于PG数据库来说也可以通过pg_resetwal命令来实现创建,由于pg_control文件损坏,需要人工指定一些参数完成pg_resetwal相关操作
pg_resetwal 使用说明

-bash-4.2$ pg_resetwal --help
pg_resetwal resets the PostgreSQL write-ahead log.

Usage:
  pg_resetwal [OPTION]... DATADIR

Options:
  -c, --commit-timestamp-ids=XID,XID
                                   set oldest and newest transactions bearing
                                   commit timestamp (zero means no change)
 [-D, --pgdata=]DATADIR            data directory
  -e, --epoch=XIDEPOCH             set next transaction ID epoch
  -f, --force                      force update to be done
  -l, --next-wal-file=WALFILE      set minimum starting location for new WAL
  -m, --multixact-ids=MXID,MXID    set next and oldest multitransaction ID
  -n, --dry-run                    no update, just show what would be done
  -o, --next-oid=OID               set next OID
  -O, --multixact-offset=OFFSET    set next multitransaction offset
  -u, --oldest-transaction-id=XID  set oldest transaction ID
  -V, --version                    output version information, then exit
  -x, --next-transaction-id=XID    set next transaction ID
      --wal-segsize=SIZE           size of WAL segments, in megabytes
  -?, --help                       show this help, then exit

Report bugs to <pgsql-bugs@lists.postgresql.org>.
PostgreSQL home page: <https://www.postgresql.org/>

确认现在业务表记录情况

-bash-4.2$ psql
psql (14.3)
Type "help" for help.

postgres=# select count(1) from ac_event;
 count  
--------
 246266
(1 row)

模拟pg_control文件异常

-bash-4.2$ ps -ef|grep postgres
postgres  37178      1  0 09:58 ?        00:00:00 /usr/pgsql-14/bin/postgres -D /var/lib/pgsql/14/data
postgres  37179  37178  0 09:58 ?        00:00:00 postgres: logger 
postgres  37181  37178  0 09:58 ?        00:00:00 postgres: checkpointer 
postgres  37182  37178  0 09:58 ?        00:00:00 postgres: background writer 
postgres  37183  37178  0 09:58 ?        00:00:00 postgres: walwriter 
postgres  37184  37178  0 09:58 ?        00:00:00 postgres: autovacuum launcher 
postgres  37185  37178  0 09:58 ?        00:00:00 postgres: stats collector 
postgres  37186  37178  0 09:58 ?        00:00:00 postgres: logical replication launcher 
root      41368  41314  0 11:06 pts/1    00:00:00 su - postgres
postgres  41369  41368  0 11:06 pts/1    00:00:00 -bash
postgres  45071  41369  0 12:07 pts/1    00:00:00 ps -ef
postgres  45072  41369  0 12:07 pts/1    00:00:00 grep --color=auto postgres
-bash-4.2$ kill -9 37178
-bash-4.2$ ps -ef|grep postgres
root      41368  41314  0 11:06 pts/1    00:00:00 su - postgres
postgres  41369  41368  0 11:06 pts/1    00:00:00 -bash
postgres  45095  41369  0 12:08 pts/1    00:00:00 ps -ef
postgres  45096  41369  0 12:08 pts/1    00:00:00 grep --color=auto postgres
-bash-4.2$ pwd
/var/lib/pgsql/14/data/global
-bash-4.2$ ls -l pg_control 
-rw-------. 1 postgres postgres 8192 May 30 12:04 pg_control
-bash-4.2$ rm -rf pg_control 
-bash-4.2$ ls -l pg_control 
ls: cannot access pg_control: No such file or directory

PG启动失败

-bash-4.2$ pg_ctl start 
pg_ctl: another server might be running; trying to start server anyway
waiting for server to start....postgres: could not find the database system
Expected to find it in the directory "/var/lib/pgsql/14/data",
but could not open file "/var/lib/pgsql/14/data/global/pg_control": No such file or directory
 stopped waiting
pg_ctl: could not start server
Examine the log output.

创建空pg_control文件启动依旧失败

-bash-4.2$ touch /var/lib/pgsql/14/data/global/pg_control
-bash-4.2$ pg_ctl start 
pg_ctl: another server might be running; trying to start server anyway
waiting for server to start....2022-05-30 12:09:43.953 CST [45215] PANIC:  
   could not read file "global/pg_control": read 0 of 296
 stopped waiting
pg_ctl: could not start server
Examine the log output.

设置next-wal-file
-l, –next-wal-file=WALFILE,这个参数设置下一个新的WAL文件的最小值，这个值可以从$PGDATA/pg_wal目录下去看最后一个WAL 文件，这个文件的id+1即可

-bash-4.2$ pwd
/var/lib/pgsql/14/data/pg_wal
-bash-4.2$ ls -l
total 16384
-rw-------. 1 postgres postgres 16777216 May 30 12:04 000000010000000000000014
drwx------. 2 postgres postgres        6 May 24 02:20 archive_status
-bash-4.2$

这个文件+1，-l 000000010000000000000015
设置next-transaction
-x, –next-transaction-id=XID,这个参数设置pg_control中的下一个XID的值，这个值可以从pg_xact目录下的文件中查询

-bash-4.2$ pwd
/var/lib/pgsql/14/data/pg_xact
-bash-4.2$ ls -ltr
total 8
-rw-------. 1 postgres postgres 8192 May 30 12:03 0000

最后一个是0000，那么下一个XID就是0001，然后乘以 1048576 (0×100000)，实际上后面直接加5个0就行了。注意，这个值是16进制的。-x 0×000100000
multixact-ids设置
-m, –multixact-ids=MXID1,MXID2，这个参数包含两个部分，MXID1和MXID2，都可以从$PGDATA/pg_multixact/offsets目录下获得。MXID1的值，首先找到最大值，+1，再乘以 65536 (0×10000，相当于后面加4个0)作为这个参数的前半部分。找到最小的值，后面加4个0，作为MXID2的值

-bash-4.2$ pwd
/var/lib/pgsql/14/data/pg_multixact/offsets
-bash-4.2$ ls -ltr
total 8
-rw-------. 1 postgres postgres 8192 May 29 22:06 0000
-bash-4.2$

-m 0×00010000, 0×00000000（由于oldest multitransaction ID不能为0,因此后续这个值需要适当调整）
multixact-offset设置
-O, –multixact-offset=OFFSET,这个参数可以从$PGDATA/pg_multixact/members目录下获得。找到最大值，+1，乘以 52352 (0xCC80)

-bash-4.2$ pwd
/var/lib/pgsql/14/data/pg_multixact/members
-bash-4.2$ ls -ltr
total 8
-rw-------. 1 postgres postgres 8192 May 24 02:20 0000

-O 0xCC80
尝试执行pg_resetwal

-bash-4.2$ pg_resetwal -l 000000010000000000000015 -x 0x000100000 -m 0x00010000,0x00000000 -O 0xCC80 $PGDATA
pg_resetwal: error: oldest multitransaction ID (-m) must not be 0

multixact-ids值不对,进行调整后处理
postmaster.pid文件需要清理
由于PG库异常关闭,需要人工清理掉该文件

-bash-4.2$ pg_resetwal -l 000000010000000000000015 -x 0x000100000 -m 0x00020000,0x00010000 -O 0xCC80 $PGDATA
pg_resetwal: error: lock file "postmaster.pid" exists
-bash-4.2$ rm -rf postmaster.pid

pg_resetwal结果预览

-bash-4.2$ pg_resetwal -l 000000010000000000000015 -x 0x000100000 -m 0x00020000,0x00010000 -O 0xCC80 $PGDATA
pg_resetwal: warning: pg_control exists but is broken or wrong version; ignoring it
Guessed pg_control values:

pg_control version number:            1300
Catalog version number:               202107181
Database system identifier:           7103392535324046312
Latest checkpoint's TimeLineID:       1
Latest checkpoint's full_page_writes: off
Latest checkpoint's NextXID:          0:3
Latest checkpoint's NextOID:          12000
Latest checkpoint's NextMultiXactId:  1
Latest checkpoint's NextMultiOffset:  0
Latest checkpoint's oldestXID:        3
Latest checkpoint's oldestXID's DB:   0
Latest checkpoint's oldestActiveXID:  0
Latest checkpoint's oldestMultiXid:   1
Latest checkpoint's oldestMulti's DB: 0
Latest checkpoint's oldestCommitTsXid:0
Latest checkpoint's newestCommitTsXid:0
Maximum data alignment:               8
Database block size:                  8192
Blocks per segment of large relation: 131072
WAL block size:                       8192
Bytes per WAL segment:                16777216
Maximum length of identifiers:        64
Maximum columns in an index:          32
Maximum size of a TOAST chunk:        1996
Size of a large-object chunk:         2048
Date/time type storage:               64-bit integers
Float8 argument passing:              by value
Data page checksum version:           0


Values to be changed:

First log segment after reset:        000000010000000000000015
NextMultiXactId:                      131072
OldestMultiXid:                       65536
OldestMulti's DB:                     0
NextMultiOffset:                      52352
NextXID:                              1048576
OldestXID:                            3
OldestXID's DB:                       0

If these values seem acceptable, use -f to force reset.

pg_resetwal进行创建pg_control并启动PG

-bash-4.2$ pg_resetwal -l 000000010000000000000015 -x 0x000100000 -m 0x00020000,0x00010000 -O 0xCC80 -f $PGDATA
pg_resetwal: warning: pg_control exists but is broken or wrong version; ignoring it
Write-ahead log reset
-bash-4.2$ pg_ctl start
waiting for server to start....2022-05-30 13:33:28.266 CST [51437] LOG:  
redirecting log output to logging collector process
2022-05-30 13:33:28.266 CST [51437] HINT:  Future log output will appear in directory "log".
 done
server started

验证数据

-bash-4.2$ psql
psql (14.3)
Type "help" for help.

postgres=#  select count(1) from ac_event;
 count  
--------
 245275
(1 row)

这种方法恢复之后,建议理解dump数据,然后导入到新库中

发表在 PostgreSQL恢复 | 标签为 pg_control丢失恢复, pg_control异常恢复, pg_control强制启动, pg_resetwal使用 | 评论关闭

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年归档：2022

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年归档：2022

PostgreSQL恢复系列:pg_filedump基本使用

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