Backup MX on a non-plesk-server

[Valentin]

Hello,

in the last couple of days I've tried to find a solution to set another server (priviously used as secondary-ns) to do the mx-fallback.
Settings the dns entries is not my problem, i've just no idea how to setup the backup-mx-qmail-server. Just copy the rctphost-file via cronjob and this works? The mails get cached and redelievered after a time?

Thanks!

Valentin