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If I add an MX record for a subdomain email address, do I also need to add a CNAME for that subdomain?

For example I want email addresses like * to be handled by a different server than * so I add the following record:

MX mysubdomain handled by with priority 10

Do I also have to add a CNAME as follows?

CNAME hr is an alias of 12.34.567.890

While I have the following A records:

A * points to 12.34.567.890
A points to 12.34.567.890
A mail points to 12.34.567.890
share|improve this question

No. As long as can be found, you are solid.

share|improve this answer does have to be an A record, it can't be a CNAME, but otherwise correct. – Chris S Jan 25 '12 at 2:14

I don't think you understand what a CNAME record is. A CNAME points an alias back to a canonical name. Your example of "hr" is what's called an A record.

If your concern is how will clients lookup the name "", the answer is through authoritative name servers.

To figure this out for yourself, try dig (or nslookup, host, equivalent for your OS) as follows:

share|improve this answer
The canonical name is the alias. It's the "standard" name, which points to a host name. – Chris S Jan 25 '12 at 2:17
… which only serves to make dmourati's point. The data portion of a CNAME resource record is not an IP address as in the question. – JdeBP Jan 25 '12 at 12:34

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