UBUNTU 20.04
It’s a bit strange. If I send mails to an Account I’ve created with virtualmin, it tooks 15 - 20 Minutes, till the Mail arrive.
I’ve activated GrayListing - but on another server (not virtualmin) I’ve also use graylisting, and mails doesn’t take as long as with the virtualmin server.
What might be the issue, that Mails take such a long time to arrive?