Linux Administration Cookbook

How it works...

All we've done here is duplicate a few files and made some sensible changes to ensure that the two processes don't interact with each other very much.

First, we created the following file:

/etc/ssh/sshd_config_2020

We then ran a couple of sed commands to change some values. Specifically, we modified the port the server would listen on, and the process ID file it would use (the PID modification is frequently overlooked).

Next, we copied the systemd unit file that comes with the OpenSSH server package on CentOS, tweaking it slightly by changing the description and pointing it to a different environment file.

We put the resulting unit file (sshd_2020.service) in a different location to the original to differentiate it from a ...