[svlug] Mail on svlug.org

Marc MERLIN marc_news at valinux.com
Mon Nov 26 09:19:03 PST 2001

On Sun, Nov 25, 2001 at 04:08:00PM -0800, Rafael Skodlar wrote:
> You have to pickup that one with Marc. I had exact the same problem.  

Actually you didn't. Your SMTP server had broken DNS and took up to 5
minutes to present an SMTP banner.

> SVLUGs MTA times out faster than other MTAs on the net if the server takes
> too long on the other side. I mentioned to Marc that my server connects
> fine with AOL but he did not think it's a good example to compare ;-)
> so I had to adjust my side.

Err, if you read the RFCs, you'll see that  an MTA has 90 sec to give you an
answer after you send a "mail from: <foo>".
If exim can't validate  your mail from in 90 secs  (because your mail server
isn't responding), it has to give you a temporary failure

> As far as I know, SVLUGs MTA won't take email from servers with IPs that
> cannot be resolved to a name.
That's not true, but any host with an IP that can't be resolved to a name is
broken, and any mail server with no reverse mapping is doubly broken.
On Sun, Nov 25, 2001 at 04:25:37PM -0800, William R. Ward wrote:
> time.  Or at least, if a message fails the checks it should go to a
> human administrator for review.
I can't start  giving you the list of  RFCs you would break by  doing such a
thing. Mails refused by mailman are held  for review, but mail that can't be
accepted  at  SMTP time  can't  easily  be sent  to  a  human without  being
accepted. Then it's too late to notify you with a bounce since your config
couldn't accept bounces.
> Yes, and there are many others with that problem.  That was one of the
> issues I faced.  The others were 1) resolv.conf didn't list my private
> name server which was needed to resolve all the machine's own IP
> addresses, and 2) MX was pointing to the wrong host.  It doesn't just
> resolve the IP, it apparently connects to the SMTP server and verifies
> the sender as a valid address.  This last step was failing because it
> was asking the wrong SMTP server, due to an MX config error on my
> part.

So, your  mail config  was broken  in several places,  you were  notified by
svlug's mail server, you were able to fix it, and you learned from it.

That seems like exim did plenty to help you :-)

Microsoft is to operating systems & security ....
                                      .... what McDonalds is to gourmet cooking
Home page: http://marc.merlins.org/   |   Finger marc_f at merlins.org for PGP key

More information about the svlug mailing list