最近重新部署我的博客，发现本地可以访问，但外网IP无法访问。大概率是防火墙问题。除了云服务器控制台上要开端口，貌似服务器本身也要设置。

首先检查firewalld安装情况。

Firewall-applet is a tray applet for firewalld. Check to see if firewalld is running on your host. Firewall-applet and firewalld are both installed separately, so there is a good chance when you remove firewall-applet, firewalld is still installed and running.

ps -ef | grep firewalld

if it is running, you can remove it by typing in:

sudo apt-get remove firewalld

如果没装，就安装：

sudo apt-get install firewalld

开放端口号

比如要开放端口号1234，则如下

sudo firewall-cmd --permanent --add-port=1234/tcp

每次新增端口号都要重启防火墙

firewall-cmd --reload

查看已开启的端口号

sudo firewall-cmd --list-ports

如开启成功则会罗列出已开启的端口号