secondary MX (was Re: [TriLUG] co-lo or at home?)
Sat, 23 Mar 2002 16:56:06 -0500 (EST)
> Do you have/know of a quick and dirty "secondary MX" HOWTO somewhere?
there's probably one out there already, but here's how to do it. i'd be
happy to provide for you, if you're interested.
the person providing secondary MX (me) needs to set up their system to
allow relaying from the system of the person receiving (you).
on red hat 7.2 with sendmail, to do that:
edit /etc/mail/access and add the following line:
then run make in /etc/mail .
the person receiving secondary MX (you) needs to list the system of the
person providing as a second MX entry with a higher value (which
translates to a lower priority) than their primary MX.
to set your DNS up to use another person as a secondary:
[lorenzin@eeyore lorenzin]$ dig 1000plus.com MX
; <<>> DiG 9.1.3 <<>> 1000plus.com MX
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 22408
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 2, ADDITIONAL: 2
;; QUESTION SECTION:
;1000plus.com. IN MX
;; ANSWER SECTION:
1000plus.com. 346 IN MX 0 mx.1000plus.com.
1000plus.com. 346 IN MX 100 mx.elfie.org.
;; AUTHORITY SECTION:
1000plus.com. 83152 IN NS NS.elfie.org.
1000plus.com. 83152 IN NS NS.TECHNOMANCER.com.
;; ADDITIONAL SECTION:
NS.elfie.org. 97645 IN A 18.104.22.168
NS.TECHNOMANCER.com. 167386 IN A 22.214.171.124
and if your system drops offline, my system starts accepting and queuing
mail for you. (i'm sure there's a default for how often it tries to
deliver it, and i'm sure it can be changed, but we didn't bother with
it's just that easy (i love linux). lemme know if you have any questions,
altho honestly that's about the extent of my clue here.
lisa lorenzin | email@example.com | http://www.1000plus.com/lisa/
of what avail is an open eye if the heart is blind? - solomon ibn gavirol