multiple MX records on same IP

[Barry Margolin]

In article <a8nbqp$fvl at pub3.rc.vix.com>, GV <atomo77 at libero.it> wrote:
>
>Barry Margolin <barmar at genuity.net> wrote in message
>news:<a8ld48$c3d at pub3.rc.vix.com>...
>......
>
>> MX records point to hostnames, not addresses.  It should be:
>> 
>> foo     A   1.2.3.4
>> foo     MX  10 foo
>> 
>> foo2    A   1.2.3.4
>> foo2    MX  10 foo (or foo2, since they're the same)
> 
>What's the difference between "foo MX 10 foo" and "foo MX 10 foo2"?

None, since they're both names for the same machine.

>Here is the complete complete problem:
>
>At the moment foo2 is only an alias (CNAME record); as a consequence,
>mail directed to foo2 is changed by some SMTP servers to foo.

As they're required to.  RFC 2822 says that addresses must only contain
canonical names, so any aliases must be translated.

>If I perform the above mentioned correction in the DNS (2 A and 2 MX
>records), will I solve my problems (Destination address of the mail
>not changed from foo2 to foo)?

Yes.

-- 
Barry Margolin, barmar at genuity.net
Genuity, Woburn, MA
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