MySQL基于gtid特性与xtrabackup的数据恢复

in 编程
关注公众号【好便宜】( ID:haopianyi222 ),领红包啦~
阿里云,国内最大的云服务商,注册就送数千元优惠券:https://t.cn/AiQe5A0g
腾讯云,良心云,价格优惠: https://t.cn/AieHwwKl
搬瓦工,CN2 GIA 优质线路,搭梯子、海外建站推荐: https://t.cn/AieHwfX9

一、gtid特性介绍:

GTID(global transaction identifier)是MySQL 5.6的新特性,可以唯一的标识一个事务,由UUID+TID组成:

在主从复制中,GTID代替了classic的复制方法,不再使用binlog+pos开启复制,而是使用master_auto_postion = 1的方式自动匹配GTID断点进行复制。

要开启GTID,只需在MySQL参数文件中添加以下参数:

gtid-mode                       = ON
enforce_gtid_consistency        = 1

二、数据恢复需求:

需要将MySQL(以下简称A库)恢复到一天前的凌晨12:00左右的状态
需要具备的前提条件如下:

  1. 开启GTID
  2. 有A库昨天凌晨12:00前的xtra备份文件
  3. 开启binlog日志(废话)

三、恢复操作:

在另一台MySQL(B库)上进行数据的恢复,这样可以避免影响线上业务

1. 将B库data目录移走,拷贝A库备份文件到B库

mv data data_20160716           #移走B库data
mv A_back_20160714 data         #移入A库备份文件
chown -R mysql12300.mysql data/

2. 开启B库,配置主从

查看data目录下xtrabackup_binlog_info文件中记录的GTID:

[root@service-test1 data]$ cat xtrabackup_binlog_info 
mysql-bin.000012        46455554        8133046e-4282-11e6-848e-026ca51d284c:1-4920155

在B库(slave)设置@@global.gtid_purged跳过备份包含的GTID,并执行change master to指定A库为主库:

mysql> SET GLOBAL gtid_purged="8133046e-4282-11e6-848e-026ca51d284c:1-4920155";
Query OK, 0 rows affected (0.00 sec)

mysql> change master to Master_Host ='10.11.21.14',Master_Port=3306,Master_User='replica',Master_Password='XXXXXXXXX',MASTER_AUTO_POSITION=1;
Query OK, 0 rows affected, 2 warnings (0.01 sec)

注意: xtrabackup_binlog_info中的GTID有时不止一个,设置@@global.gtid_purged时指定多个即可,以逗号隔开

四、在A库binlog中找到恢复点并进行恢复

需要特别注意的是,在上述操作后,不要直接start slave,否则B库也又会跑到当前A库的状态

将A库binlog转换为sql语句:

mysqlbinlog -vv mysql-bin.000011 > mysql-bin.000011.sql

找到前一天凌晨12:00左右的位置并记录GTID:

# at 561467475
#160521  0:24:31 server id 212177500  end_log_pos 561467523 CRC32 0x216072ca    GTID [commit=yes]
SET @@SESSION.GTID_NEXT= '542ef021-9a64-11e5-bc49-025d3d22c211:1348360'/*!*/;

在B库开启slave并指定恢复到的位置:

mysql> start slave until SQL_BEFORE_GTIDS='542ef021-9a64-11e5-bc49-025d3d22c211:1348360';
Query OK, 0 rows affected (0.00 sec)

当执行到了指定的GTID,SQL线程便会停止,但IO线程还会继续复制:

mysql> show slave status\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 10.30.21.11
                  Master_User: replica
                  Master_Port: 7500
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000011
          Read_Master_Log_Pos: 810203081
               Relay_Log_File: relay-bin.000002
                Relay_Log_Pos: 5707357
        Relay_Master_Log_File: mysql-bin.000011
             Slave_IO_Running: Yes
            Slave_SQL_Running: No
              Replicate_Do_DB:
          Replicate_Ignore_DB:
           Replicate_Do_Table:
       Replicate_Ignore_Table:
      Replicate_Wild_Do_Table: 
  Replicate_Wild_Ignore_Table:
                   Last_Errno: 0
                   Last_Error:
                 Skip_Counter: 0
          Exec_Master_Log_Pos: 561467475
              Relay_Log_Space: 254443161
              Until_Condition: SQL_BEFORE_GTIDS
               Until_Log_File:
                Until_Log_Pos: 0
           Master_SSL_Allowed: No
           Master_SSL_CA_File:
           Master_SSL_CA_Path:
              Master_SSL_Cert:
            Master_SSL_Cipher:
               Master_SSL_Key:
        Seconds_Behind_Master: NULL
Master_SSL_Verify_Server_Cert: No
                Last_IO_Errno: 0
                Last_IO_Error:
               Last_SQL_Errno: 0
               Last_SQL_Error:
  Replicate_Ignore_Server_Ids:
             Master_Server_Id: 21117500
                  Master_UUID: 63f38fe7-9e3b-11e5-9554-02eeb2c1042f
             Master_Info_File: /data1/mysql10070/data/master.info
                    SQL_Delay: 0
          SQL_Remaining_Delay: NULL
      Slave_SQL_Running_State:
           Master_Retry_Count: 86400
                  Master_Bind:
      Last_IO_Error_Timestamp:
     Last_SQL_Error_Timestamp:
               Master_SSL_Crl:
           Master_SSL_Crlpath:
           Retrieved_Gtid_Set: 542ef021-9a64-11e5-bc49-025d3d22c211:1341313-1368005
            Executed_Gtid_Set: 44226252-9e38-11e5-9540-02212401d46f:1,
542ef021-9a64-11e5-bc49-025d3d22c211:1-1348359,
63f38fe7-9e3b-11e5-9554-02eeb2c1042f:1
                Auto_Position: 1
1 row in set (0.00 sec)

好啦,想看昨天凌晨的哪些数据呀?都在B库里啦~~~

附:常见问题

在设置@@global.gtid_purged时,可能会遇到报错:

mysql> SET GLOBAL gtid_purged="8133046e-4282-11e6-848e-026ca51d284c:1-4920155";
ERROR 1840 (HY000): @@GLOBAL.GTID_PURGED can only be set when @@GLOBAL.GTID_EXECUTED is empty.

这是因为这台MySQL的@@GLOBAL.GTID_EXECUTED并不是空的,执行以下reset master操作就好了:

mysql> SET GLOBAL gtid_purged="8133046e-4282-11e6-848e-026ca51d284c:1-4920155";
ERROR 1840 (HY000): @@GLOBAL.GTID_PURGED can only be set when @@GLOBAL.GTID_EXECUTED is empty.
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------------------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set                         |
+------------------+----------+--------------+------------------+-------------------------------------------+
| mysql-bin.000002 |      191 |              |                  | 3857c25c-2caa-11e6-b61b-021feddc3827:1-14 |
+------------------+----------+--------------+------------------+-------------------------------------------+
1 row in set (0.00 sec)

mysql> reset master;
Query OK, 0 rows affected (0.01 sec)

mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000001 |      151 |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)

mysql> SET GLOBAL gtid_purged="8133046e-4282-11e6-848e-026ca51d284c:1-4920155";
Query OK, 0 rows affected (0.00 sec)
关注公众号【好便宜】( ID:haopianyi222 ),领红包啦~
阿里云,国内最大的云服务商,注册就送数千元优惠券:https://t.cn/AiQe5A0g
腾讯云,良心云,价格优惠: https://t.cn/AieHwwKl
搬瓦工,CN2 GIA 优质线路,搭梯子、海外建站推荐: https://t.cn/AieHwfX9
扫一扫关注公众号添加购物返利助手,领红包
Comments are closed.

推荐使用阿里云服务器

超多优惠券

服务器最低一折,一年不到100!

朕已阅去看看