How does CentOS modify the SSH port (how to modify the SSH port)

 

This article will share  how CentOS modifies the SSH port (how to modify the SSH port)

1. Log in to the centos server

2. Modify the SSH configuration file

vi /etc/ssh/sshd_config

3. Add a new port

# 查看当前ssh服务器端口号
netstat -tunlp | grep "ssh"

 

Opened for the first time and found that Port 22 is commented

Remove the previous #, and add a Port 202. The added listening port number should preferably be within the range of 10000~65535, that is, 2 to the 16th power. Doing this prevents port 202 from being connected and can also use port 22 to connect.

SSH related commands

# 重启sshd 服务：
systemctl restart sshd

# 查看sshd服务是否正常启动：
systemctl status sshd

# 检查端口是否处于监听状态：
netstat -ntulp | grep sshd

4. Firewall release

# 查看防火墙状态
firewall-cmd --state

# 防火墙如果关闭，则需要打开防火墙，执行命令：
# 打开防火墙
systemctl start firewalld
# 开机时启动firewall
systemctl enable firewalld.service

# 防火墙放行端口 202
firewall-cmd --zone=public --add-port=202/tcp --permanent

# 查看已开启端口
firewall-cmd --list-port

# 重启防火墙
systemctl restart firewalld

# 重启ssh服务
systemctl restart sshd

After the test is successful, just comment out port 22!