Hi there
I've just had a user complain that our mail server is not routing mail
properly to his machine. He has several virtual domains and mail to these
machines is not being routed as he expected. I think that qmail is doing
the right thing, and his DNS entries are incorrect, but I'd like more
knowledgeable folk to verify this.
Mail to [EMAIL PROTECTED] goes directly to centaur.graham.ru.ac.za:
pa.ru.ac.za -> centaur.graham.ru.ac.za
The user thinks it should go via terrapin.ru.ac.za:
pa.ru.ac.za -> terrapin.ru.ac.za -> centaur.graham.ru.ac.za
Here's what I think qmail does:
1) Look up the MX record of pa.ru.ac.za:
rucus:~$ dnsquery -t MX pa.ru.ac.za
[snip]
pa.ru.ac.za. 3D IN CNAME centaur.graham.ru.ac.za.
[snip]
2) Resolve centaur.graham.ru.ac.za
3) Look up the MX record of centaur.graham.ru.ac.za
rucus:~$ dnsquery -t MX centaur.graham.ru.ac.za
Query failed (h_errno = 4) : No address associated with name
rucus:~$
4) No MX. Let's see if it has an A record:
rucus:~$ dnsquery -t MX centaur.graham.ru.ac.za
[snip]
centaur.graham.ru.ac.za. 3D IN A 146.231.32.200
[snip]
5) It does. Send the mail to centaur.graham.ru.ac.za
Of all his virtual hosts, I believe only graham.ru.ac.za is configured
correctly.
1) Look up the MX record of graham.ru.ac.za
rucus:~$ dnsquery -t mx graham.ru.ac.za
[snip]
graham.ru.ac.za. 3D IN MX 10 terrapin.ru.ac.za
[snip]
2) Send the mail to terrapin.ru.ac.za
Is this correct?
Thanks.
- Keith (who wishes he had a Qmail book to look this up in ;)
--
Keith Burdis - MSc (Computer Science) - Rhodes University, South Africa
IRC: Panthras JAPH QEFH
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