[plug] explicit e-mail routing; postfix/sendmail

[Leon Blackwell]

On Wed, Aug 15, 2001 at 02:40:37PM +0800, Mike Holland wrote:
> Q1) Why doesnt mail to ... at tmd-liv1.mobilenet.telstra.net work?
>     A manual telnet to port 25 works OK.

I'm fairly sure that the SMTP specification says that an MTA should
wait for a valid DNS resolution of the destination host's MX --
otherwise weird things would happen everytime a nameserver played up.


> Q2) How can I get procmail/sendmail (on my ISP) to forward mails
>     directly to the given server, when the MX record has gone?

You can direct mail to a particular host by IP address, which
shouldn't require any DNS resolution or MX lookups (I think).

The format for addressing such a mail is:

username@[xxx.xxx.xxx.xxx]

For example, the following should email me without too much trouble:

leon@[203.29.96.62]

I'm not sure that there's a configuration solution that will force
sendmail to send the mails directly.  You could possibly mess with
disabling DNS completely for sendmail as described in the FAQ:
http://www.sendmail.org/faq/section3.html#3.22
but that looks pretty horrible to me  :)


-- 
 Leon Blackwell                | Never be afraid to try something new. 
 http://www.lostrealm.com/     | Remember, amateurs built the ark. 
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