Installing Backup MX

[noratx]

I have just read the documentation about installing the toaster as a backup MX, but i have some questions.

1. Does the versions matter? My primary MX runs on toaster 5.06. Can i run 5.09 without any problems?
2. What exactly do i need to install? Is Apache/Mysql needed? And filters, do i need them? Doesn't the primary MX takes care of spam and viruses?

I will runt the backup MX on a cable provider that has blocked port 25, just as i do with my primary MX. In my primary MX, i have set qmail to use the providers smtp, is this possible for the backup MX as well, or will that cause problems?

And then another question, when it comes to backup user accounts and mails, what, apart from ~vpopmail/domains/ and the mysql databases do i have to include in the backup?

Thank you in advance.
/Rickard

[noratx]

Isn't there anyone who can give me som advice please?