远程连接MySQL出于安全考虑,一般都关闭了远程访问,但有时候需要提供远程访问数据库的服务,下面我们介绍两种开启mysql远程连接的方法。
Mysql默认root用户只能本地访问,不能远程连接管理mysql数据库,Linux如何开启mysql远程连接?设置步骤如下:
1、GRANT命令创建远程连接mysql授权用户itlogger
代码如下 | 复制代码 |
mysql -u root -p |
第一句增加itlogger用户授权通过本地机(localhost)访问,密码“www.itlogger.com”。第二句则是授与itlogger用户从任何其它主机发起的访问(通配符%)。
2、设置防火墙允许3306端口
vi /etc/sysconfig/IPtables
添加-A RH-Firewall-1-INPUT -m state –state NEW -m tcp -p tcp –dport 3306 -j ACCEPT
(注意添加在-A RH-Firewall-1-INPUT -j REJECT –reject-with icmp-host-prohibited之前,否则可能导致规则不生效)
重启防火墙service iptables restart
3、附:Mysql无法远程连接的常见问题
1)查看Mysql的端口是否正确,通过netstat -ntlp查看端口占用情况,一般情况下端口是3306。
2)报错:ERROR 2003 (HY000): Can’t connect to MySQL server on ’192.168.51.112′ (111)
查看/etc/my.cnf中,skip-networking 是否已被注掉,需要注掉。
3)报错:ERROR 2003 (HY000): Can’t connect to MySQL server on ’192.168.51.112′ (113)
查看是否iptables没有允许mysql连接,通过:service iptables stop临时关闭测试是否可以正常远程访问,如果可以,按上面方面设置iptable允许3306端口
4)远程访问mysql速度很慢的解决方法
修改/etc/my.cnf或my.ini
[mysqld]下添加
代码如下 | 复制代码 |
skip-name-resolve skip-grant-tables |
方法二 修改my.ini
第一步:修改my.cnf文件
使用文本编辑器去编辑MySQL服务器的配置文件my.cnf
如果你使用Debian Linux,文件位置在: /etc/mysql/my.cnf
如果你使用Red Hat Linux/Fedora/Centos Linux,文件位置在: /etc/my.cnf
如果你使用FreeBSD,文件位置在: /var/db/mysql/my.cnf
如果使用VI编辑,直接使用命令
代码如下 | 复制代码 |
# vi /etc/my.cnf |
第二步:如果文件打开,按照下面内容进行
[mysqld]
确保skip-networking是被注释的,或者被删除,然后添加下面一行内容
bind-address=你的服务器IP
例如,你的服务器IP是65.55.55.2,然后需要配置例如如下的内容:
代码如下 | 复制代码 |
[mysqld] user = mysql pid-file = /var/run/mysqld/mysqld.pid socket = /var/run/mysqld/mysqld.sock port = 3306 basedir = /usr datadir = /var/lib/mysql tmpdir = /tmp language = /usr/share/mysql/English bind-address = 65.55.55.2 # skip-networking .... .. ....
|
这里面
bind-address : 你需要绑定的IP地址.
skip-networking : 开启 skip-networking 选项可以彻底关闭MySQL的TCP/IP连接方式,在一些文档中也提到在单机运行的 MySQL 推荐开启该选项,现在看,不太靠谱。
第三步:保存并且关闭文件
重启你的MySQL服务器,在命令行输出
# /etc/init.d/mysql restart
第四步:绑定远程IP地址的管理权限
连接MySQL服务器:
$ mysql -u root -p mysql
绑定权限到新的数据表(这一步可以借助phpmyadmin这类的工具简单完成,这里只是个例子)
如果我们需要绑定一个远程ip 202.54.10.20到新建的foo数据库下的bar用户中,在命令行中输入:
代码如下 | 复制代码 |
mysql> CREATE DATABASE foo; mysql> GRANT ALL ON foo.* TO bar@'202.54.10.20' IDENTIFIED BY 'PASSWORD';
|
如何绑定一个已经存在的数据库呢?
代码如下 | 复制代码 |
mysql> update db set Host='202.54.10.20' where Db='webdb'; mysql> update user set Host='202.54.10.20' where user='webadmin'; |
第四步:推出MySQL
输入下面的命令:
代码如下 | 复制代码 |
mysql> quit; 第五步:打开3306 |
端口
需要将TCP端口3306开启,使用iptables或者BSD的pf 防火墙
Linux下iptables的例子
/sbin/iptables -A INPUT -i eth0 -p tcp --destination-port 3306 -j ACCEPT
或者如果你只需要允许特定的服务器,ip为10.5.1.3,可以这样:
/sbin/iptables -A INPUT -i eth0 -s 10.5.1.3 -p tcp --destination-port 3306 -j ACCEPT
或者仅仅允许自己子网内的远程连接范围192.168.1.0/24
/sbin/iptables -A INPUT -i eth0 -s 192.168.1.0/24 -p tcp --destination-port 3306 -j ACCEPT
最后保存所有规则
# service iptables save
FreeBSD / OpenBSD pf 的规则( /etc/pf.conf)
pass in on $ext_if proto tcp from any to any port 3306
或者允许允许ip:10.5.1.3
pass in on $ext_if proto tcp from 10.5.1.3 to any port 3306 flags S/SA synproxy state
第六步:测试
你远程主机上面打开cmd,输入:
mysql -u webadmin –h 65.55.55.2 –p
在这里
-u webadmin: webadmin 是MySQL服务器的用户
-h IP or 服务器名称: 65.55.55.2 is MySQL 服务器IP地址
-p : 密码
你同样可以使用telnet来连接到3306端口
$ telnet 65.55.55.2 3306

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