How to backup postfix?

Question

I am putting together a list of things that I need to backup, on my website.

I am using postfix for handling my mail.

Which files in /etc/postfix (if any) do I need to backup?

My goal is that after I restore from backup files, I should have all my previous mail as well.

So my question can be broken into two parts:

1. How do I backup postfix (i.e. which files do I take a copy of)?
2. Once I have a backup, how can I restore so that I have access to my previous mail (is it simply a case of copying the restored files to /etc/postfix)?

My server is running a headless Ubuntu 10.0.4

Answer 1

Backup everything in /etc/postfix, it is simpler that way.

As for the email. If the email hasn't been touched, then Postfix has no influence on it. It just delivers mail, it doesn't provide access to it. (You need access to the filesystem, or an IMAP, POP3, etc server for that)

If the email has been damaged, then restoring it from backup is trickier.

MTAs, like postfix, don't store the mail. They deliver it somewhere. Where that is is determined by the configuration.

My system, which doesn't use Postfix (although the principles are the same) delivers everything to /home/$userid/Maildir/.

… except that some users have Procmail set up to filter mail, so some of it ends up in different places.

Since I said it depends on the configuration, let's have another example. An older system I used delivered to /var/spool/mail/$userid (a completely different part of the filesystem).