MySQL日志管理

最近在配置主从服务器，对接触的一些日志文件，进行一下总结。

是否开启

首先就是确定是否启用了二进制日志

mysql> show variables like '%log_bin%'; +---------------------------------+--------------------------------------------------------+ | Variable_name | Value | +---------------------------------+--------------------------------------------------------+ | log_bin | ON | | log_bin_basename | /usr/local/var/mysql/dingjiacaideMacBook-Pro-bin | | log_bin_index | /usr/local/var/mysql/dingjiacaideMacBook-Pro-bin.index | | log_bin_trust_function_creators | OFF | | log_bin_use_v1_row_events | OFF | | sql_log_bin | ON | +---------------------------------+--------------------------------------------------------+ 6 rows in set (0.00 sec) mysql>

上面的变量log_bin 值为on说明已经启用了，如果没有启用的话，就在my.cnf文件加入下面一行

[mysqld] log_bin

查看二进制内容

方法一：

mysql> show binlog events;//当前在用的日志 +------------------------------------+-----+----------------+-----------+-------------+-------------------------------------------+ | Log_name | Pos | Event_type | Server_id | End_log_pos | Info | +------------------------------------+-----+----------------+-----------+-------------+-------------------------------------------+ | dingjiacaideMacBook-Pro-bin.000001 | 4 | Format_desc | 1 | 123 | Server ver: 5.7.12-log, Binlog ver: 4 | | dingjiacaideMacBook-Pro-bin.000001 | 123 | Previous_gtids | 1 | 150 | | | dingjiacaideMacBook-Pro-bin.000001 | 150 | Anonymous_Gtid | 1 | 211 | SET @@SESSION.GTID_NEXT= 'ANONYMOUS' | | dingjiacaideMacBook-Pro-bin.000001 | 211 | Query | 1 | 281 | BEGIN | | dingjiacaideMacBook-Pro-bin.000001 | 281 | Table_map | 1 | 323 | table_id: 108 (mysync.t) | | dingjiacaideMacBook-Pro-bin.000001 | 323 | Write_rows | 1 | 359 | table_id: 108 flags: STMT_END_F | | dingjiacaideMacBook-Pro-bin.000001 | 359 | Xid | 1 | 386 | COMMIT /* xid=51 */ | +------------------------------------+-----+----------------+-----------+-------------+-------------------------------------------+ 14 rows in set (0.00 sec)

方法二：

mysql $ sudo mysqlbinlog --start-position=150 /usr/local/var/mysql/dingjiacaideMacBook-Pro-bin.000001 // 从150开始查看二进制文件内容

mysqlbinlog具体有提供哪些参数，这里就不详细说明了，通过–help可以查看帮助，这个在主从服务器同步是出现错误的时候，用来查找问题很管用

显示二进制数目

mysql> show master logs; +------------------------------------+-----------+ | Log_name | File_size | +------------------------------------+-----------+ | dingjiacaideMacBook-Pro-bin.000001 | 784 | +------------------------------------+-----------+ 1 row in set (0.00 sec) mysql>

查看当前状态

mysql> show master status\G // 查看从服务器的状态把master改为slave即可 *************************** 1. row *************************** File: dingjiacaideMacBook-Pro-bin.000001 Position: 784 Binlog_Do_DB: Binlog_Ignore_DB: Executed_Gtid_Set: 1 row in set (0.00 sec) mysql>

删除二进制日志

mysql> reset master; Query OK, 0 rows affected (0.08 sec) mysql>

刷新日志

mysql> flush logs;//刷新日志 Query OK, 0 rows affected (0.07 sec) mysql> show master logs;//查看日志，从结果可知多了000002这个日志 +------------------------------------+-----------+ | Log_name | File_size | +------------------------------------+-----------+ | dingjiacaideMacBook-Pro-bin.000001 | 211 | | dingjiacaideMacBook-Pro-bin.000002 | 150 | +------------------------------------+-----------+ 2 rows in set (0.00 sec) mysql>

上面提到的是在配主从服务器时，用到的二进制日志文件

除了上面提到日志文件之外，在平时用的比较多的就是错误日志了，如果在对MySQL不是很熟悉的情况下，怎样快速得知日志的路径，只要想下面进行操作：

方法一：

mysql $ ps -ef| grep mysql//查看进程 0 70529 1 0 1:30下午 ?? 0:00.03 /bin/sh /usr/local/Cellar/mysql/5.7.12//bin/mysqld_safe --datadir=/usr/local/var/mysql --pid-file=/usr/local/var/mysql/dingjiacaideMacBook-Pro.local.pid 74 70735 70529 0 1:30下午 ?? 0:03.38 /usr/local/Cellar/mysql/5.7.12/bin/mysqld --basedir=/usr/local/Cellar/mysql/5.7.12/ --datadir=/usr/local/var/mysql --plugin-dir=/usr/local/Cellar/mysql/5.7.12//lib/plugin --user=_mysql --log-error=/usr/local/var/mysql/dingjiacaideMacBook-Pro.local.err --pid-file=/usr/local/var/mysql/dingjiacaideMacBook-Pro.local.pid --socket=/tmp/mysql.sock --port=3306 501 79053 61539 0 5:06下午 ttys003 0:00.00 grep mysql mysql $

方法二：

mysql> show variables like '%log_error%';//全局变量查看 +---------------------+--------------------------------------------------------+ | Variable_name | Value | +---------------------+--------------------------------------------------------+ | binlog_error_action | ABORT_SERVER | | log_error | /usr/local/var/mysql/dingjiacaideMacBook-Pro.local.err | | log_error_verbosity | 3 | +---------------------+--------------------------------------------------------+ 3 rows in set (0.00 sec) mysql>

当然了，还有其他的日志，这里就不一一说明了，想知道他们的所在位置就通过show variables like ‘%log_%’;这个命令查看