"Richard Goodman" <r.goodman@11harvard.com> wrote:
My home DSL has been down for over 48 hours and it appears that it will be down for several more days. (I spare you the gory details). I am concerned about losing mail coming into various domains at that site.
I was in a similar situation not too long ago when prolonged outages, address changes and ISP port blocking became too much to deal with. Losing my mail was fine, but the family went nuts when I was on the road and we had an outage. I wound up moving my SMTP to a $2/mo. hosting plan that will queue mail for me until I poll using POP via fetchmail. I've permanently pointed my MX record there, as their reliability is far better than mine (residential cable). I know this isn't as attractive as doing it yourself, and it might not be an option if you have a lot of domains to deal with. But it might be a quick fix if that outage is going to go on for a long time.
[...] I have modified the secondary DNS records for those domains (on a machine at my office - also on DSL) with an higher cost MX record pointing to a machine at the office also running RH 7.3 and sendmail, which I assume will pick up and queue the mail. The DNS TTLs are reasonably short, fortunately.
If the TTLs are short, hopefully senders will queue it until your backup is in place.
I've done this following O'Reilly/Sendmail book 2nd edition, but its not always crystal clear if you don't already understand it! Is there anything else I have to do on the backup machine (pointed to by the new MX records), particularly is there anything I have to do to its sendmail config files?
As Mike mentioned, there is configuration required on the backup server to accept for your domains. Nice to have an employer that doesn't mind that though!
Any other pointers or "gotcha"s to this whole process?
I was having fun doing it all via postfix at home, but I'm glad I made the move. Not only do I have less twiddling to do on my own time, but when my stuff was all torn down and shipped here from Phoenix, I didn't lost anything. Good luck! - Bob