In this section, we will discover some advanced security settings that are needed for most Ubuntu servers that are in a production environment, especially when they contain critical services. This advanced configuration is important because it will directly touch the behavior of services besides Ubuntu Server itself.
By definition, SSH is a secure communication protocol, but there are some additional enhancements that we can apply to take this security a step ahead.
Let's start with the default Ubuntu SSH configuration. The
/etc/ssh/sshd_config file, which is very secure as it allows authentication keys to be used, uses privilege separation and allows only SSH protocol 2. The only questionable ...