背景:闲来想着用navicat访问下centos上的数据库,发现连接不上。。。尴尬。。
如图:一直在连接。。然后报了一个unknown error。。
![](https://img-blog.csdnimg.cn/20181117105614430.png)
![](https://img-blog.csdnimg.cn/20181117105637570.png)
解决:
1、查看一下防火墙状态
[root@VM_0_15_centos ~]# systemctl status iptables.service
● iptables.service - IPv4 firewall with iptables
Loaded: loaded (/usr/lib/systemd/system/iptables.service; enabled; vendor preset: disabled)
Active: inactive (dead) since Sat 2018-11-17 10:13:48 CST; 45min ago
Process: 2312 ExecStop=/usr/libexec/iptables/iptables.init stop (code=exited, status=0/SUCCESS)
Process: 454 ExecStart=/usr/libexec/iptables/iptables.init start (code=exited, status=0/SUCCESS)
Main PID: 454 (code=exited, status=0/SUCCESS)
Nov 17 10:10:22 VM_0_15_centos systemd[1]: Starting IPv4 firewall with iptables...
Nov 17 10:10:22 VM_0_15_centos iptables.init[454]: iptables: Applying firewall rules: [ OK ]
Nov 17 10:10:22 VM_0_15_centos systemd[1]: Started IPv4 firewall with iptables.
Nov 17 10:13:48 VM_0_15_centos systemd[1]: Stopping IPv4 firewall with iptables...
Nov 17 10:13:48 VM_0_15_centos iptables.init[2312]: iptables: Setting chains to policy ACCEPT: filter [ OK ]
Nov 17 10:13:48 VM_0_15_centos iptables.init[2312]: iptables: Flushing firewall rules: [ OK ]
Nov 17 10:13:48 VM_0_15_centos iptables.init[2312]: iptables: Unloading modules: [ OK ]
Nov 17 10:13:48 VM_0_15_centos systemd[1]: Stopped IPv4 firewall with iptables.
2、开启3306端口
/sbin/iptables -I INPUT -p tcp --dport 3306 -j ACCEPT
3、保存
[root@VM_0_15_centos ~]# service iptables save
iptables: Saving firewall rules to /etc/sysconfig/iptables:[ OK ]
4、连接成功
![](https://img-blog.csdnimg.cn/20181117144830871.png)
5、关闭3306端口
[root@VM_0_15_centos ~]# /sbin/iptables -I INPUT -p tcp --dport 3306 -j DROP