MySQL备份与恢复之冷备（1）_Mysql

用一句话概括冷备，就是把数据库服务，比如MySQL，Oracle停下来，然后使用拷贝、打包或者压缩命令对数据目录进行备份。如果数据出现异常，则可以通过备份数据恢复。冷备一般需要定制计划，比如什么时候做备份，每次对哪些数据进行备份等等。但是由于这样的备份占用过多的空间，对大数据量的环境下不一定适合，故生产环境很少使用。

冷备示意图

MySQL备份与恢复之冷备（1）

冷备实验

第一步，创建测试数据库，插入测试数据

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									mysql> use larrydb;

									Database changed

									mysql> show tables;

									+-------------------+

									| Tables_in_larrydb |

									+-------------------+

									| access  |

									+-------------------+

									1 row in set (0.00 sec)

									mysql> drop table access;

									Query OK, 0 rows affected (0.00 sec)

									mysql> clear

									mysql> show tables;

									Empty set (0.00 sec)

									mysql> 

									mysql> create table class(

									 -> cid int,

									 -> cname varchar(30));

									Query OK, 0 rows affected (0.01 sec)

									mysql> show create table class \G;

									*************************** 1. row ***************************

									 Table: class

									Create Table: CREATE TABLE `class` (

									 `cid` int(11) DEFAULT NULL,

									 `cname` varchar(30) DEFAULT NULL

									) ENGINE=InnoDB DEFAULT CHARSET=latin1

									1 row in set (0.00 sec)

									ERROR: 

									No query specified

									mysql> create table stu(

									 -> sid int,

									 -> sname varchar(30),

									 -> cid int) engine=myisam;

									Query OK, 0 rows affected (0.00 sec)

									mysql> show create table stu \G;

									*************************** 1. row ***************************

									 Table: stu

									Create Table: CREATE TABLE `stu` (

									 `sid` int(11) DEFAULT NULL,

									 `sname` varchar(30) DEFAULT NULL,

									 `cid` int(11) DEFAULT NULL

									) ENGINE=MyISAM DEFAULT CHARSET=utf8

									1 row in set (0.00 sec)

									ERROR: 

									No query specified

									mysql> insert into class values(1,'linux'),(2,'oracle');

									Query OK, 2 rows affected (0.00 sec)

									Records: 2 Duplicates: 0 Warnings: 0

									mysql> desc class;

									+-------+-------------+------+-----+---------+-------+

									| Field | Type | Null | Key | Default | Extra |

									+-------+-------------+------+-----+---------+-------+

									| cid | int(11) | YES | | NULL | |

									| cname | varchar(30) | YES | | NULL | |

									+-------+-------------+------+-----+---------+-------+

									2 rows in set (0.00 sec)

									mysql> desc stu;

									+-------+-------------+------+-----+---------+-------+

									| Field | Type | Null | Key | Default | Extra |

									+-------+-------------+------+-----+---------+-------+

									| sid | int(11) | YES | | NULL | |

									| sname | varchar(30) | YES | | NULL | |

									| cid | int(11) | YES | | NULL | |

									+-------+-------------+------+-----+---------+-------+

									3 rows in set (0.00 sec)

									mysql> insert into stu values(1,'larry01',1),(2,'larry02',2);

									Query OK, 2 rows affected (0.00 sec)

									Records: 2 Duplicates: 0 Warnings: 0

									mysql> select * from stu;

									+------+---------+------+

									| sid | sname | cid |

									+------+---------+------+

									| 1 | larry01 | 1 |

									| 2 | larry02 | 2 |

									+------+---------+------+

第二步，停掉MySQL

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									[root@serv01 ~]# /etc/init.d/mysqld stop

									Shutting down MySQL... SUCCESS!

第三步，创建备份目录，并修改拥有者和所属组

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									[root@serv01 ~]# mkdir /databackup

									[root@serv01 ~]# chown mysql.mysql /databackup/ -R

									[root@serv01 ~]# ll /databackup/ -d

									drwxr-xr-x. 2 mysql mysql 4096 Sep 10 17:46 /databackup/

									[root@serv01 ~]# cd /databackup/

第四步，冷备（使用tar命令）

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									[root@serv01 databackup]# tar -cvPzf mysql01.tar.gz

第五步，测试冷备的数据是否正常，我们删除掉data下的所有数据

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									[root@serv01 databackup]# rm -rf /usr/local/mysql/data/*

第六步，删除所有数据后数据库不能启动

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									[root@serv01 databackup]# /etc/init.d/mysqld start

									Starting MySQL.. ERROR! The server quit without updating PID file (/usr/local/mysql/data/serv01.host.com.pid).

第七步，恢复数据（使用tar命令）

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									[root@serv01 databackup]# tar -xvPf mysql01.tar.gz

第八步，启动MySQL，然后登录MySQL，查看数据是否丢失，如果数据正常代表冷备成功

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									[root@serv01 databackup]# /etc/init.d/mysqld start

									Starting MySQL.. SUCCESS! 

									[root@serv01 ~]# mysql

									Welcome to the MySQL monitor. Commands end with ; or \g.

									Your MySQL connection id is 1

									Server version: 5.5.29-log Source distribution

									Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved.

									Oracle is a registered trademark of Oracle Corporation and/or its

									affiliates. Other names may be trademarks of their respective

									owners.

									Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

									mysql> use larrydb;

									Database changed

									mysql> select * from class;

									+------+--------+

									| cid | cname |

									+------+--------+

									| 1 | linux |

									| 2 | oracle |

									+------+--------+

									2 rows in set (0.00 sec)

									mysql> select * from stu;

									+------+---------+------+

									| sid | sname | cid |

									+------+---------+------+

									| 1 | larry01 | 1 |

									| 2 | larry02 | 2 |

									+------+---------+------+

									2 rows in set (0.00 sec)