Changes

In fact, the above diagram does not include reading mail messages, but this acts as a starting point in order to run a basic email server. Although will be learning to administer the mail services in the diagram above, we will not required you to go into tremendous depth (just the minimum requirements). For example, we will not go over every aspect of the Postfix MTA service, but you should know what it represents and what is its main purpose, as opposed to the following: [https://en.wikipedia.org/wiki/Postfix_%28software%29#Architecture complex diagram 1] , [https://www.credativ.de/blog/postfix-architecture-overview complex diagram 2].