Subdomains and MX records

[ploughingon]

Hi

I'm trying to establish if i need to add an MX record, I think i do, but a colleague is insisting i do not.

we already have a valid NS record and mx record working

eg
NS example.co.uk 10.0.0.1
MX example.co.uk 10.1.0.1

we want a subdomain which will be

NS subdomain.example.co.uk 10.0.0.2
MX subdomain.example.co.uk 10.1.0.1 (same smtp server as example.co.uk)

My colleague insists we dont need the mx record for subdomain.example.co.uk as the smtp server for the primary domain is the same and traffic for the subdomain will be handled with that for the primary domain.

I'm not so sure and could do with some advice.

 

[Serbtastic]

It is only necessary if you plan on receiving mail for subdomain.example.co.uk on a different mail server than example.co.uk. If all mail goes to the same mail server then MX records for the subdomain are not necessary.

 

[GunnarD]

I should enter MX records for subdomains that receives mail, just to remined that it is a maildomain, and to be sure that changes in the future in example.co.uk domain has some unwanted errors.