补充防火墙配置.

Signed-off-by: lion.chan <cy187lion@sina.com>

Software/Applications/NFS/NFS_服务安装和配置.md

@@ -59,6 +59,15 @@ sudo systemctl stop nfs-server
 sudo systemctl disable nfs-server
 ```
 
+## 防火墙配置
+
+```sh
+firewall-cmd --permanent --zone public --add-service mountd
+firewall-cmd --permanent --zone public --add-service rpc-bind
+firewall-cmd --permanent --zone public --add-service nfs
+firewall-cmd --reload
+```
+
 ## 挂载 NFS 文件系统
 
 ```bash