Every so often it's natural that a mistake will be made and an instance will either need to be wiped back to its factory state (just the bare operating system) or restored to a previously taken snapshot.
So, you want to restore a snapshot you have taken on our old style networking setup to a brand new shiny instance on our new style networking setup and it doesn't work! Learn how to build a new instance from an old-style snapshot.
Postifx is a very popular mail server that can be setup on Linux relatively easily and it is extremely configurable and easy to maintain. Paired with Dovecot for POP/IMAP functionality, you can have a basic mail server setup within minutes.
Snapshots are a great way to back up your instance in case the unthinkable happens. These can be initiated manually, but Civo also offers automated snapshots which will automatically update based on any schedule you like.