Create MX Record for Subdomain

Question

I have two Zimbra mail servers. One of them serve for stuff and the other one serve for student. So I want to create use two different mail template like sfuff_mail@domain.edu and student_mail@student.domain.edu.

I have no problem for sfuff_mail@domain.edu.

For student I created a sub domain like studentlogin.domain.edu

I use Bind 9 on Centos 7.

But when a try a mail a have error message like "The address not found".

You can see my config.

    studentlogin.domain.edu.     IN  MX      10   mail.student.domain.edu.
    studentlogin.domain.edu.     IN  A       XX.XXX.XXX.XXX
    studentlogin.domain.edu.     IN  TXT     "v=spf1 a mx ptr a:mail.student.domain.edu mx:mail.student.domain.edu ip4:XX.XXX.XXX.XXX ~all"

What I should do?

Please help.

Best regards.

bofh · Answer 1 · 2017-09-05T22:33:30.240

This is how I would configured it, based on the slightly vague information, provided. You could make adjustments, as needed:

$TTL 1D
@                       IN      SOA     ns.domain.edu. support.domain.edu. (
                                        2017090501      ; serial
                                        1D              ; refresh
                                        1H              ; retry
                                        1W              ; expire
                                        3H )            ; minimum

                                NS      ns.domain.edu.
                                MX 10   mail.domain.edu.
                                TXT     "v=spf1 mx ~all"

ns                      IN      A       10.10.10.2
mail                    IN      A       10.10.10.10

student                 IN      MX 10   mail.student.domain.edu.
student                 IN      TXT     "v=spf1 mx ~all"
mail.student            IN      A       10.0.0.10



$ dig domain.edu any

;; ANSWER SECTION:
domain.edu.             86400   IN      SOA     ns.domain.edu. support.domain.edu. 2017090501 86400 3600 604800 10800
domain.edu.             86400   IN      NS      ns.domain.edu.
domain.edu.             86400   IN      MX      10 mail.domain.edu.
domain.edu.             86400   IN      TXT     "v=spf1 mx ~all"

;; ADDITIONAL SECTION:
ns.domain.edu.          86400   IN      A       10.10.10.2
mail.domain.edu.        86400   IN      A       10.10.10.10



$ dig student.domain.edu any

;; ANSWER SECTION:
student.domain.edu.     86400   IN      MX      10 mail.student.domain.edu.
student.domain.edu.     86400   IN      TXT     "v=spf1 mx ~all"

;; AUTHORITY SECTION:
domain.edu.             86400   IN      NS      ns.domain.edu.

;; ADDITIONAL SECTION:
mail.student.domain.edu. 86400  IN      A       10.0.0.10
ns.domain.edu.          86400   IN      A       10.10.10.2

P.S. Using a particular SPF mechanism is an administrative decision in most of the cases, rather than technical.

score 0 · Answer 2 · answered Aug 28 '17 at 16:21

0

Try removing the "." after the MX record. --> studentlogin.domain.edu

Also be sure to have separate IP addresses as you can only have one rDNS entry per IP and a mail server must have its hostname set as rDNS to be RFC compliant. Similar question here: How should I setup separate MX records for a subdomain?

PS Any reason why you use ~all instead of -all in your SPF rule? (for reference see https://wordtothewise.com/2014/06/authenticating-spf/)

answered Aug 28 '17 at 16:21

Chris

76
6

Thank you very much Chris. My rDNS record is correct. In addition when i use same subdomain and same mail address such as student.domain.edu subdomain and student_mail@student.domain.edu mail it works. But when i use different subdomain and mail address like studentlogin.domain.edu and student_mail@domain.edu it doesnt work. – zegufe Aug 28 '17 at 20:31

Create MX Record for Subdomain

2 Answers2