Change ssh port of CentOS 7

To change SSH port of CentOS 7 please follow those steps-

1. At first backup the default configuration file. It is always a best practice to backup files before modification, so that we can restore it if anything unwanted happends.

   sudo cp /etc/ssh/sshd_config /etc/ssh/sshd_config.bak
   

2. Then open the sshd_config file -

   sudo vi /etc/ssh/sshd_config
   

   and change the port number(ex. 2122) -

   Port 2122
   #AddressFamily any
   #ListenAddress 0.0.0.0
   #ListenAddress ::
   

3. By default, SELinux only allows port 22 for SSH. What you need to do is enable the newly created port through SELinux. To do that, run the commands below

   sudo semanage port -a -t ssh_port_t -p tcp 2122
   

4. Add the new port to the firewall to allow access

   sudo firewall-cmd --permanent --zone=public --add-port=2122/tcp
   

5. Reload the firewall configuration file -

   sudo firewall-cmd --reload
   

6. Now restart SSH service

   sudo systemctl restart sshd.service
   

7. Now exit and try to connect to new port

   ssh username@192.168.10.240 -p 2022
   

Enjoy