ibdata1文件損壞時恢復單表測試

来源:https://www.cnblogs.com/aaron8219/archive/2018/08/03/9417033.html
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  Preface       ibdata1 file is a shared system tablespace of innodb engine.Although we always set variable of "innodb_file_per_table" to "on" which means put the data of table into their individual ibd files.The ibdata file will still store undo log of our innodb tables.As the ibdata1 file is inevitable to make the MySQL database running properly.Today,I'm gonna demonstrate a way to rescue the table in an instance whose ibdata file is destroied by a certain way such as write several unmeaningful characters into it.   Porcedure   Backup the instance using Xtrabackup first.
 1 [root@zlm1 13:46:27 ~]
 2 #innobackupex --defaults-file=/data/mysql/mysql3306/my3306.cnf --user=root --password=Passw0rd /data/backup
 3 180805 13:46:40 innobackupex: Starting the backup operation
 4 ... //Omitted.
 5 
 6 [root@zlm1 13:47:14 /data/backup]
 7 #ls -l
 8 total 4
 9 drwxr-x--- 7 root root 4096 Aug  5 13:47 2018-08-05_13-46-40
10 
11 [root@zlm1 13:47:17 /data/backup]

 

Check the target table which we want to rescue in plan.

 1 zlm@192.168.56.100:3306 [sysbench]>show tables;
 2 +--------------------+
 3 | Tables_in_sysbench |
 4 +--------------------+
 5 | sbtest1            |
 6 | sbtest2            |
 7 | sbtest3            |
 8 | sbtest4            |
 9 +--------------------+
10 4 rows in set (0.00 sec)
11 
12 zlm@192.168.56.100:3306 [sysbench]>select count(*) from sbtest4;
13 +----------+
14 | count(*) |
15 +----------+
16 |    10000 |
17 +----------+
18 1 row in set (0.05 sec)
19 
20 zlm@192.168.56.100:3306 [sysbench]>delete from sbtest4 limit 1000;
21 Query OK, 1000 rows affected (0.17 sec)
22 
23 zlm@192.168.56.100:3306 [sysbench]>select count(*) from sbtest4;
24 +----------+
25 | count(*) |
26 +----------+
27 |     9000 |
28 +----------+
29 1 row in set (0.00 sec)

 

Destroy the ibdata1 file with "dd" command.

 1 [root@zlm1 13:57:01 ~]
 2 #cd /data/mysql/mysql3306/data
 3 
 4 [root@zlm1 13:59:35 /data/mysql/mysql3306/data]
 5 #ls -l
 6 total 433892
 7 -rw-r----- 1 mysql mysql        56 Mar 18 15:10 auto.cnf
 8 -rw-r----- 1 mysql mysql     81490 Aug  5 13:50 error.log
 9 -rw-r----- 1 mysql mysql       882 Jul 31 16:36 ib_buffer_pool
10 -rw-r----- 1 mysql mysql 104857600 Aug  5 13:45 ibdata1
11 -rw-r----- 1 mysql mysql 104857600 Aug  5 13:45 ib_logfile0
12 -rw-r----- 1 mysql mysql 104857600 Aug  5 13:45 ib_logfile1
13 -rw-r----- 1 mysql mysql 104857600 Jul  1 14:32 ib_logfile2
14 -rw-r----- 1 mysql mysql  12582912 Aug  5 13:45 ibtmp1
15 -rw-r----- 1 mysql mysql      3924 Aug  5 13:53 innodb_status.3799
16 -rw-r----- 1 mysql mysql         0 Jul 14 02:52 innodb_status.3828
17 -rw-r----- 1 mysql mysql      4008 Jun  1 21:38 innodb_status.4131
18 drwxr-x--- 2 mysql mysql      4096 Jul  7 09:57 mrbs
19 drwxr-x--- 2 mysql mysql      4096 Mar 18 15:10 mysql
20 -rw-r----- 1 mysql mysql         5 Aug  5 13:45 mysql.pid
21 drwxr-x--- 2 mysql mysql      8192 Mar 18 15:10 performance_schema
22 -rw-r----- 1 mysql mysql       177 Jun  4 16:48 relay-bin.000001
23 -rw-r----- 1 mysql mysql        19 Jun  4 16:48 relay-bin.index
24 -rw-r----- 1 mysql mysql    526773 Aug  5 13:45 slow.log
25 drwxr-x--- 2 mysql mysql      8192 Mar 18 15:10 sys
26 drwxr-x--- 2 mysql mysql      4096 Jul 31 16:35 sysbench
27 -rw-r----- 1 mysql mysql  11610419 Jul 29 09:52 zlm1.log
28 
29 [root@zlm1 13:59:38 /data/mysql/mysql3306/data]
30 #dd if=/dev/zero of=./ibdata1 bs=1024 count=262144
31 262144+0 records in
32 262144+0 records out
33 268435456 bytes (268 MB) copied, 1.61997 s, 166 MB/s
34 
35 [root@zlm1 14:02:34 /data/mysql/mysql3306/data]
36 #ls -l|grep ibdata1
37 -rw-r----- 1 mysql mysql 268435456 Aug  5 14:06 ibdata1 //The ibdata1 turned out to be 256M and filled with zero.

 

Restart the MySQL instance.

 1 zlm@192.168.56.100:3306 [sysbench]>exit
 2 Bye
 3 
 4 [root@zlm1 14:13:06 ~]
 5 #mysqladmin shutdown
 6 
 7 [root@zlm1 14:13:10 ~]
 8 #ps aux|grep mysqld
 9 root      4002  0.0  0.0 112640   960 pts/0    R+   14:13   0:00 grep --color=auto mysqld
10 
11 [root@zlm1 14:13:15 ~]
12 #./mysqld.sh
13 
14 [root@zlm1 14:13:53 ~]
15 #mysql
16 ERROR 2003 (HY000): Can't connect to MySQL server on '192.168.56.100' (111)
17 
18 [root@zlm1 14:13:56 ~]
19 #mysql
20 ERROR 2003 (HY000): Can't connect to MySQL server on '192.168.56.100' (111)
21 
22 [root@zlm1 14:13:58 ~]
23 #cd /data/mysql/mysql3306/data
24 
25 [root@zlm1 14:14:07 /data/mysql/mysql3306/data]
26 #tail error.log
27 ... /Omitted.
28 2018-08-05T12:13:53.242723Z 0 [Note] --secure-file-priv is set to NULL. Operations related to importing and exporting data are disabled
29 2018-08-05T12:13:53.242806Z 0 [Note] mysqld (mysqld 5.7.21-log) starting as process 4008 ...
30 2018-08-05T12:13:53.249168Z 0 [Note] InnoDB: PUNCH HOLE support available
31 2018-08-05T12:13:53.249207Z 0 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
32 2018-08-05T12:13:53.249213Z 0 [Note] InnoDB: Uses event mutexes
33 2018-08-05T12:13:53.249218Z 0 [Note] InnoDB: GCC builtin __sync_synchronize() is used for memory barrier
34 2018-08-05T12:13:53.249222Z 0 [Note] InnoDB: Compressed tables use zlib 1.2.3
35 2018-08-05T12:13:53.249227Z 0 [Note] InnoDB: Using Linux native AIO
36 2018-08-05T12:13:53.249426Z 0 [Note] InnoDB: Number of pools: 1
37 2018-08-05T12:13:53.249507Z 0 [Note] InnoDB: Using CPU crc32 instructions
38 2018-08-05T12:13:53.251488Z 0 [Note] InnoDB: Initializing buffer pool, total size = 100M, instances = 1, chunk size = 100M
39 2018-08-05T12:13:53.256630Z 0 [Note] InnoDB: Completed initialization of buffer pool
40 2018-08-05T12:13:53.257913Z 0 [Note] InnoDB: If the mysqld execution user is authorized, page cleaner thread priority can be changed. See the man page of setpriority().
41 2018-08-05T12:13:53.280321Z 0 [Note] InnoDB: Highest supported file format is Barracuda.
42 12:13:53 UTC - mysqld got signal 11 ;
43 This could be because you hit a bug. It is also possible that this binary
44 or one of the libraries it was linked against is corrupt, improperly built,
45 or misconfigured. This error can also be caused by malfunctioning hardware.
46 Attempting to collect some information that could help diagnose the problem.
47 As this is a crash and something is definitely wrong, the information
48 collection process might fail.
49 
50 key_buffer_size=8388608
51 read_buffer_size=2097152
52 max_used_connections=0
53 max_threads=100
54 thread_count=0
55 connection_count=0
56 It is possible that mysqld could use up to 
57 key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 227127 K  bytes of memory
58 Hope that's ok; if not, decrease some variables in the equation.
59 
60 Thread pointer: 0x0
61 Attempting backtrace. You can use the following information to find out
62 where mysqld died. If you see no messages after this, something went
63 terribly wrong...
64 stack_bottom = 0 thread_stack 0x30000
65 mysqld(my_print_stacktrace+0x35)[0xf4a495]
66 mysqld(handle_fatal_signal+0x4a4)[0x7ce2f4]
67 /lib64/libpthread.so.0(+0xf130)[0x7f6bbee76130]
68 mysqld(_Z26page_cur_search_with_matchPK11buf_block_tPK12dict_index_tPK8dtuple_t15page_cur_mode_tPmS9_P10page_cur_tP8rtr_info+0x148)[0x1074478]
69 mysqld(_Z27btr_cur_search_to_nth_levelP12dict_index_tmPK8dtuple_t15page_cur_mode_tmP9btr_cur_tmPKcmP5mtr_t+0x1598)[0x11806d8]
70 mysqld(_Z30btr_pcur_open_on_user_rec_funcP12dict_index_tPK8dtuple_t15page_cur_mode_tmP10btr_pcur_tPKcmP5mtr_t+0x212)[0x1184b62]
71 mysqld[0x11df28d]
72 mysqld(_Z19dict_load_sys_tableP12dict_table_t+0x69)[0x11e0609]
73 mysqld(_Z9dict_bootv+0xdfb)[0x11bf48b]
74 mysqld(_Z34innobase_start_or_create_for_mysqlv+0x3212)[0x11150a2]
75 mysqld[0x100023a]
76 mysqld(_Z24ha_initialize_handlertonP13st_plugin_int+0x51)[0x819721]
77 mysqld[0xd39226]
78 mysqld(_Z40plugin_register_builtin_and_init_core_sePiPPc+0x3e4)[0xd397a4]
79 mysqld[0x7c48f7]
80 mysqld(_Z11mysqld_mainiPPc+0x92f)[0x7c7e9f]
81 /lib64/libc.so.6(__libc_start_main+0xf5)[0x7f6bbd857af5]
82 mysqld[0x7be479]
83 The manual page at http://dev.mysql.com/doc/mysql/en/crashing.html contains
84 information that should help you find out what is causing the crash.
85 
86 [root@zlm1 14:14:36 /data/mysql/mysql3306/data]
87 
88 //Okay,becasue of the lack of normal ibdata1 file in datadir,the instance cannot be started again.
89 //Then,how can we resuce the data in target table 'sbtest4'?
90 //First of all,let's get the ibd and frm file of it from the crashed server.

 

Copy ibd and frm file of table "sbtest4" to another newly initialized instance on zlm2.

1 [root@zlm1 14:20:39 /data/mysql/mysql3306/data/sysbench]
2 #scp sbtest4.* zlm2:/data/backup
3 sbtest4.frm                                                                                                        100% 8632     8.4KB/s   00:00    
4 sbtest4.ibd                                                                                                        100%   10MB  10.0MB/s   00:01

 

Install mysql-utilities package on zlm2.

 1 [root@zlm2 14:23:13 ~]
 2 #mysqlfrm --help
 3 -bash: mysqlfrm: command not found
 4 
 5 [root@zlm2 14:23:17 ~]
 6 #yum install mysql-utilities
 7 Loaded plugins: fastestmirror
 8 base                                                                                                                          | 3.6 kB  00:00:00     
 9 epel/x86_64/metalink                                                                                                          | 7.0 kB  00:00:00     
10 epel                                                                                                                          | 3.2 kB  00:00:00     
11 extras                                                                                                                        | 3.4 kB  00:00:00     
12 updates                                                                                                                       | 3.4 kB  00:00:00     
13 (1/5): epel/x86_64/group_gz                                                                                                   |  88 kB  00:00:00     
14 (2/5): epel/x86_64/updateinfo                                                                                                 | 932 kB  00:00:00     
15 (3/5): extras/7/x86_64/primary_db                                                                                             | 173 kB  00:00:00     
16 (4/5): epel/x86_64/primary                                                                                                    | 3.6 MB  00:00:01     
17 (5/5): updates/7/x86_64/primary_db                                                                                            | 4.3 MB  00:00:04     
18 Loading mirror speeds from cached hostfile
19  * base: mirrors.shu.edu.cn
20  * epel: mirrors.tongji.edu.cn
21  * extras: mirrors.163.com
22  * updates: mirrors.163.com
23 epel                                                                                                                                     12629/12629
24 Resolving Dependencies
25 --> Running transaction check
26 ---> Package mysql-utilities.noarch 0:1.3.6-1.el7 will be installed
27 --> Processing Dependency: mysql-connector-python for package: mysql-utilities-1.3.6-1.el7.noarch
28 --> Running transaction check
29 ---> Package mysql-connector-python.noarch 0:1.1.6-1.el7 will be installed
30 --> Finished Dependency Resolution
31 
32 ... //Omitted.
33 
34 Installed:
35   mysql-utilities.noarch 0:1.3.6-1.el7                                                                                                               
36 
37 Dependency Installed:
38   mysql-connector-python.noarch 0:1.1.6-1.el7                                                                                                        
39 
40 Complete!

 

Restore the table structure by mysqlfrm.

 1 [root@zlm2 14:30:41 ~]
 2 #cd /data/backup/
 3 
 4 [root@zlm2 14:30:48 /data/backup]
 5 #ls -l|grep sbtest4
 6 -rw-r----- 1 root  root      8632 Aug  5 14:30 sbtest4.frm
 7 -rw-r----- 1 root  root  10485760 Aug  5 14:30 sbtest4.ibd
 8 
 9 [root@zlm2 14:31:25 /data/backup]
10 #mysqlfrm --basedir=/usr/local/mysql --port=8219 --diagnostic ./sbtest4.frm
11 # WARNING The --port option is not used in the --diagnostic mode.
12 # WARNING: Cannot generate character set or collation names without the --server option.
13 # CAUTION: The diagnostic mode is a best-effort parse of the .frm file. As such, it may not identify all of the components of the table correctly. This is especially true for damaged files. It will also not read the default values for the columns and the resulting statement may not be syntactically correct.
14 # Reading .frm file for ./sbtest4.frm:
15 # The .frm file is a TABLE.
16 # CREATE TABLE Statement:
17 
18 CREATE TABLE `sbtest4` (
19   `id` int(11) NOT NULL AUTO_INCREMENT, 
20   `k` int(11) NOT NULL, 
21   `c` char(360) NOT NULL, 
22   `pad` char(180) NOT NULL, 
23 PRIMARY KEY `PRIMARY` (`id`),
24 KEY `k_4` (`k`)
25 ) ENGINE=InnoDB;
26 
27 #...done.

 

Create a same table structure in the new instance using the restored "create table" statement.

 1 [root@zlm2 14:39:02 /data/backup]
 2 #mysql
 3 Welcome to the MySQL monitor.  Commands end with ; or \g.
 4 Your MySQL connection id is 7
 5 Server version: 5.7.21-log MySQL Community Server (GPL)
 6 
 7 Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
 8 
 9 Oracle is a registered trademark of Oracle Corporation and/or its
10 affiliates. Other names may be trademarks of their respective
11 owners.
12 
13 Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
14 
15 zlm@192.168.56.101:3306 [(none)]>show databases;
16 +--------------------+
17 | Database           |
18 +--------------------+
19 | information_schema |
20 | mrbs               |
21 | mysql              |
22 | performance_schema |
23 | sys                |
24 +--------------------+
25 5 rows in set (0.00 sec)
26 
27 zlm@192.168.56.101:3306 [(none)]>create database sysbench;
28 Query OK, 1 row affected (0.00 sec)
29 
30 zlm@192.168.56.101:3306 [(none)]>use sysbench
31 Database changed
32 zlm@192.168.56.101:3306 [sysbench]>show tables;
33 Empty set (0.00 sec)
34 
35 zlm@192.168.56.101:3306 [sysbench]>CREATE TABLE `sbtest4` (
36     ->   `id` int(11) NOT NULL AUTO_INCREMENT, 
37     ->   `k` int(11) NOT NULL, 
38     ->   `c` char(360) NOT NULL, 
39     ->   `pad` char(180) NOT NULL, 
40     -> PRIMARY KEY `PRIMARY` (`id`),
41     -> KEY `k_4` (`k`)
42     -> ) ENGINE=InnoDB;
43 ERROR 1074 (42000): Column length too big for column 'c' (max = 255); use BLOB or TEXT instead
44 zlm@192.168.56.101:3306 [sysbench]>CREATE TABLE `sbtest4` (
45     ->   `id` int(11) NOT NULL AUTO_INCREMENT, 
46     ->   `k` int(11) NOT NULL, 
47     ->   `c` char(120) NOT NULL, 
48     ->   `pad` char(60) NOT NULL, 
49     -> PRIMARY KEY `PRIMARY` (`id`),
50     -> KEY `k_4` (`k`)
51     -> ) ENGINE=InnoDB;
52 ERROR 1146 (42S02): Table 'sysbench.sbtest4' doesn't exist
53 zlm@192.168.56.101:3306 [sysbench]>CREATE TABLE `sbtest4_bak` (
54     ->   `id` int(11) NOT NULL AUTO_INCREMENT, 
55     ->   `k` int(11) NOT NULL, 
56     ->   `c` char(120) NOT NULL, 
57     ->   `pad` char(60) NOT NULL, 
58     -> PRIMARY KEY `PRIMARY` (`id`),
59     -> KEY `k_4` (`k`)
60     -> ) ENGINE=InnoDB;
61 Query OK, 0 rows affected (0.01 sec)
62 
63 
64 zlm@192.168.56.101:3306 [sysbench]>rename table sbtest4_bak to sbtest4;
65 Query OK, 0 rows affected (0.00 sec)
66 
67 zlm@192.168.56.101:3306 [sysbench]>show tables;
68 +--------------------+
69 | Tables_in_sysbench |
70 +--------------------+
71 | sbtest4            |
72 +--------------------+
73 1 row in set (0.00 sec)
74 
75 zlm@192.168.56.101:3306 [sysbench]>show create table sbtest4\G
76 *************************** 1. row ***************************
77        Table: sbtest4
78 Create Table: CREATE TABLE `sbtest4` (
79   `id` int(11) NOT NULL AUTO_INCREMENT,
80   `k` int(11) NOT NULL,
81   `c` char(120) NOT NULL,
82   `pad` char(60) NOT NULL,
83   PRIMARY KEY (`id`),
84   KEY `k_4` (`k`)
85 ) ENGINE=InnoDB DEFAULT CHARSET=utf8
86 1 row in set (0.00 sec)
87 
88 zlm@192.168.56.101:3306 [sysbench]>select count(*) from sbtest4;
89 +----------+
90 | count(*) |
91 +----------+
92 |        0 |
93 +----------+
94 1 row in set (0.00 sec)

 

Discard the tablesapce of new table "sbtest4".

 1 zlm@192.168.56.101:3306 [sysbench]>alter table sbtest4 discard tablespace;
 2 Query OK, 0 rows affected (0.00 sec)
 3 
 4 [root@zlm2 15:01:45 /data/mysql/mysql3306/data/sysbench]
 5 #ls -l
 6 total 16
 7 -rw-r----- 1 mysql mysql   61 Aug  5 14:39 db.opt
 8 -rw-r----- 1 mysql mysql 8632 Aug  5 14:54 sbtest4.frm
 9 
10 //After the discard operation,the new ibd file has gone.

 

Copy the ibd file of table "sbtest4" to the sysbench directory in datadir(notice the owner of file).

 1 [root@zlm2 15:05:42 /data/backup]
 2 #cp sbtest4.ibd /data/mysql/mysql3306/data/sysbench/
 3 
 4 [root@zlm2 15:05:54 /data/backup]
 5 #ll /data/mysql/mysql3306/data/sysbench/ |grep sbtest4
 6 -rw-r----- 1 mysql mysql     8632 Aug  5 14:54 sbtest4.frm
 7 -rw-r----- 1 root  root  10485760 Aug  5 15:05 sbtest4.ibd
 8 
 9 [root@zlm2 <

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  • 1.前言 什麼是熱更新 游戲或者軟體更新時,無需重新下載客戶端進行安裝,而是在應用程式啟動的情況下,在內部進行資源或者代碼更新 Unity目前常用熱更新解決方案 HybridCLR,Xlua,ILRuntime等 Unity目前常用資源管理解決方案 AssetBundles,Addressable, ...
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