Migration for a start December 18, 2020 10:28 AM, "John Levine via mailop" <mailop@mailop.org> wrote:
> As we all know, MX records have a priority number, and mail senders > are supposed to try the highest priority/lowest number servers first, > then fall back to the lower priority. > > I understand why secondary MX made sense in the 1980s, when the net > was flakier, there was a lot of dialup, and there were hosts that only > connected for a few hours or even a few minutes a day. > > But now, in 2020, is there a point to secondary servers? Mail servers > are online all the time, and if they fail for a few minutes or hours, > the client servers will queue and retry when they come back. > > Secondary servers are a famous source of spam leaks, since they > generally don't know the set of valid mailboxes and often don't keep > their filtering in sync? What purpose do they serve now? > > R's, > John > > PS: I understand the point of multiple MX with the same priority for > load balancing. The question is what's the point of a high priorty > server that's always up, and a lower priority server that's, I dunno, > probably always up, too. > > _______________________________________________ > mailop mailing list > mailop@mailop.org > https://list.mailop.org/listinfo/mailop _______________________________________________ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop
