4.1 问题
启用binlog日志，具体要求如下：
启用binlog日志，把日志文件存放到系统的/mylog目录下，日志文件为db50
手动创建3个新的日志文件
删除编号3之前的日志文件
4.2 步骤
实现此案例需要按照如下步骤进行。
步骤一：启用binlog日志
1）修改配置文件，并重启服务。
[root@dbsvr1 ~]# vim /etc/my.cnf
[mysqld]
server_id=1 //指定server_id
log-bin=/mylog/db50 //指定日志目录及名称
:wq
[root@dbsvr1 ~]# mkdir /mylog //创建目录
[root@dbsvr1 ~]# chown mysql /mylog //修改所有者
[root@dbsvr1 ~]# systemctl restart mysqld.service //重启服务
2）查看日志信息
[root@dbsvr1 ~]#
[root@localhost ~]# mysql -uroot -p123qqq...A //管理员登录
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.7.17-log MySQL Community Server (GPL)
Copyright (c) 2000, 2016, 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> show master status; //查看日志信息
+-------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+-------------+----------+--------------+------------------+-------------------+
| db50.000001 | 154 | | | |
+-------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
mysql>
3）手动创建3个新的日志文件
mysql>
mysql> flush logs; //刷新日志
Query OK, 0 rows affected (0.14 sec)
mysql> flush logs; //刷新日志
Query OK, 0 rows affected (0.11 sec)
mysql> flush logs; //刷新日志
Query OK, 0 rows affected (0.12 sec)
mysql> system ls /mylog/ //查看日志文件
db50.000001 db50.000002 db50.000003 db50.000004 db50.index
mysql>
mysql> show master status; //查看日志信息
+-------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+-------------+----------+--------------+------------------+-------------------+
| db50.000004 | 154 | | | |
+-------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
mysql>
4）删除编号3之前的日志文件
mysql>
mysql> purge master logs to "db50.000003"; //删除日志
Query OK, 0 rows affected (0.05 sec)
mysql> system ls /mylog/ //查看日志文件
db50.000003 db50.000004 db50.index
mysql>
mysql> system cat /mylog/db50.index //查看索引文件
/mylog/db50.000003
/mylog/db50.000004
mysql>
