CNAME & MX record confusion.

John Wobus jw354 at
Mon Mar 3 21:12:47 UTC 2008

If you make a DNS name into an alias for another DNS name
using a CNAME record, e.g., CNAME

then all the MXs for also apply
to its alias, ''.  Same for any other
DNS records for ''.  Any record
for also applies to ''.

As simple as this concept appears as stated above, it's
implications often confuse people.  For example, it does not matter
that your purpose for setting up the CNAME was strictly
for the benefit of web serving.

Furthermore, you cannot have other DNS records for an alias
such as  To do so would be like saying it's
an alias and it also isn't.  An alias is an alias and can be nothing 

When someone, who is used to setting up 'name virtual'
webservers using CNAMEs runs into problems with these restrictions, 
they switch to using A records instead of a CNAME.  If
has one A record with number, then you also
deploy this record: A

Then you can give that name its own MX record(s).

John Wobus

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