send e-mail without use sendmail

[Les Mikesell]

Bob Marcan wrote:
> Ed Greshko wrote:
>> Frank Cox wrote:
>>> On Wed, 31 Oct 2007 12:05:11 -0500
>>> Les Mikesell <lesmikesell at gmail.com> wrote:
>>>
>>>> You must have a real domain name to send email. 
>>> Is there any technical reason (other than "we hate spammers") why 
>>> email can't
>>> be sent to an IP address instead of a domain name?
>>>
>>> I know that mail sent to joeblow at 123.456.789.001 doesn't work, but 
>>> have never
>>> really understood why...
>>
>> It is call "fault tolerance".  In general, sending to a single IP 
>> address is
>> has a single point of failure.  If that system is down...email doesn't 
>> move.
>>  When you send to company.com there is what is known as an MX record that
>> returns all the IP addresses that accept email for company.com and 
>> weights
>> for the sending side to decided who to sent to first and failing that
>> second, etc.
>>
>> Sending to IP addresses doesn't scale and isn't manageable.
>>
> 
> joeblow@[123.456.789.001] does work.


Well it might with a real IP address... None of the octets would be 
greater than 255 in a real one - and they don't have leading 0's.

-- 
   Les Mikesell
    lesmikesell at gmail.com