Group Manager accounts hosted with Kolab Now use their own domains for email and groupware. MX records in the DNS zone for the domain will therefore list the Kolab Now SMTP servers. Customers sometimes ask us if they could use MX records from their own domain. This article explains in detail why that is likely unreasonably burdensome.
$ nslookup > set type=mx > kolab.org Server: 8.8.8.8 Address: 8.8.8.8#53 Non-authoritative answer: kolab.org mail exchanger = 10 mx01.kolabnow.com. kolab.org mail exchanger = 10 mx02.kolabnow.com. Authoritative answers can be found from: >
Customers frequently ask whether they could use their own MX records, such that these lookups look slightly more consistent;
$ nslookup > set type=mx > kolab.org Server: 8.8.8.8 Address: 8.8.8.8#53 Non-authoritative answer: kolab.org mail exchanger = 10 mx01.kolab.org. kolab.org mail exchanger = 10 mx02.kolab.org. Authoritative answers can be found from: >
The short answer is “Yes you can”. The proper answer is “Yes, but you shouldn’t”.
While this is technically possible, another question is whether you should: The values of MX records MUST have A record types, and MAY NOT be CNAME record types. As such, the following is invalid:
; WARNING: INVALID CONFIGURATION, DO NOT USE
MX 10 mx01.kolab.org.
MX 10 mx02.kolab.org.
mx01 CNAME mx01.kolabnow.com.
mx02 CNAME mx02.kolabnow.com.
To use your own MX records, you must therefore maintain a list of A record types. This is ill-advised, and strongly recommended against, as Kolab Now may in the future change the server system’s IP addresses without notifying you.
; WARNING: BAD IDEA, THIS WILL STOP WORKING
MX 10 mx01.kolab.org.
MX 10 mx02.kolab.org.
mx01 A 95.128.36.40
A 95.128.36.41
A 95.128.36.42
mx02 A 95.128.36.40
A 95.128.36.41
A 95.128.36.42
See Also
- Documentation: DNS Zone Settings for Group Managers
- FAQ: Can I specify an additional MX record for my domain?