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Rick Moen [rick at linuxmafia.com]
Thu, 6 Jul 2006 17:56:55 -0700
I used to wonder what "unroutable address" meant in SMTP Delivery Status Notification messages, as it has always seemed more than a bit vague. It turns out, it is vague. ;-> It's the default Exim return value if a message gets evaluated against all the Exim "router" handling routines to see if it meets any of their criteria for acceptance. If not, it falls through and generates return value text "unrouteable address" by default (https://www.exim.org/exim-html-4.40/doc/html/spec_3.html#SECT3.10). The question then becomes why, in each case. For TAG subscriber Barry O'Donovan <gazette at barryodonovan.com), only a little checking was required to find out:
$ dig -t mx barryodonovan.com +short ;; connection timed out; no servers could be reached $ dig -t a barryodonovan.com +short ;; connection timed out; no servers could be reached $ whois barrydonovan.com | more Whois Server Version 2.0 Domain names in the .com and .net domains can now be registered with many different competing registrars. Go to https://www.internic.net for detailed information. No match for "BARRYDONOVAN.COM". >>> Last update of whois database: Thu, 06 Jul 2006 20:35:56 EDT <<< [...]Because Barry's domain no longer exists, I've been getting one of the below-cited nastygrams every time anyone posts to TAG. So, I'm setting his subscription to "nomail" in case he fixes his domain. ('Course, he might never figure out why he's ceased to receive TAG mail, but that's the breaks.)
----- Forwarded message from Mail Delivery System <Mailer-Daemon at linuxmafia.com> ----- Return-path: <> Envelope-to: rick at linuxmafia.com Delivery-date: Thu, 06 Jul 2006 16:58:46 -0700 Received: from Debian-exim by linuxmafia.com with local (Exim 4.61 #1 (EximConfig 2.0)) id 1Fydk5-0000uS-5f ; Thu, 06 Jul 2006 16:58:45 -0700 X-Failed-Recipients: gazette at barryodonovan.com Auto-Submitted: auto-repliedFrom: Mail Delivery System <Mailer-Daemon@linuxmafia.com> To: TAG <tag@lists.linuxgazette.net> To: tag-bounces at lists.linuxgazette.net Subject: Mail delivery failed: returning message to senderMessage-Id: <E1Fydk5-0000uS-5f at linuxmafia.com>Date: Thu, 06 Jul 2006 16:58:45 -0700X-SA-Do-Not-Run: Ja X-SA-Exim-Connect-IP: <locally generated> X-SA-Exim-Mail-From: X-SA-Exim-Scanned: No (on linuxmafia.com); SAEximRunCond expanded to false This message was created automatically by mail delivery software. A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed: gazette at barryodonovan.com Unrouteable address ------ This is a copy of the message, including all the headers. ------ [ ... ] ----- End forwarded message -----
Rick Moen [rick at linuxmafia.com]
Thu, 6 Jul 2006 18:16:55 -0700
I wrote:
> Because Barry's domain no longer exists, I've been getting one of the > below-cited nastygrams every time anyone posts to TAG. So, I'm setting > his subscription to "nomail" in case he fixes his domain.
...and should have updated the subject header to reflect my deciding on that remedy, rather than just removing his subscription, as I'd intended upon starting my post. (Unfortunately, I sent before thinking.)
Benjamin A. Okopnik [ben at linuxgazette.net]
Fri, 7 Jul 2006 00:14:23 -0400
On Thu, Jul 06, 2006 at 05:56:55PM -0700, Rick Moen wrote:
> > I used to wonder what "unroutable address" meant in SMTP Delivery Status > Notification messages, as it has always seemed more than a bit vague. > It turns out, it is vague. ;-> It's the default Exim return value if > a message gets evaluated against all the Exim "router" handling routines to > see if it meets any of their criteria for acceptance. If not, it falls > through and generates return value text "unrouteable address" by default > (https://www.exim.org/exim-html-4.40/doc/html/spec_3.html#SECT3.10). The > question then becomes why, in each case. For TAG subscriber Barry > O'Donovan <gazette at barryodonovan.com), only a little checking was > required to find out: > > $ dig -t mx barryodonovan.com +short > ;; connection timed out; no servers could be reached > $ dig -t a barryodonovan.com +short > ;; connection timed out; no servers could be reached
I got a slightly different (and slightly puzzling) reply:
ben at Fenrir:~$ dig -t mx barryodonovan.com +short ;; reply from unexpected source: 66.174.92.14#53, expected 66.174.95.44#53 ;; Warning: ID mismatch: expected ID 45929, got 20410 ;; reply from unexpected source: 66.174.92.14#53, expected 66.174.95.44#53 ;; Warning: ID mismatch: expected ID 45929, got 20410 ;; connection timed out; no servers could be reached
> $ whois barrydonovan.com | more
^^^^^^^^^^^^^^^^
Whoops! That should, of course, been "whois barryodonovan.com" (note the
'o' between the first and the last names):
[snip] Domain Name: BARRYODONOVAN.COM Registrar: DIRECT INFORMATION PVT LTD D/B/A PUBLICDOMAINREGISTRY.COM Whois Server: whois.PublicDomainRegistry.com Referral URL: https://www.PublicDomainRegistry.com Name Server: NS2.OPENSOLUTIONS.IE Name Server: NS1.OPENSOLUTIONS.IE Status: ACTIVE EPP Status: ok Updated Date: 25-Jul-2005 Creation Date: 13-May-2004 Expiration Date: 13-May-2007 [snip]
> Because Barry's domain no longer exists, I've been getting one of the
> below-cited nastygrams every time anyone posts to TAG. So, I'm setting
> his subscription to "nomail" in case he fixes his domain. ('Course, he
> might never figure out why he's ceased to receive TAG mail, but that's
> the breaks.)
Despite the above differences, I still agree that this is the right thing to do. When mail gets repeatedly bounced for non-trivial causes - and the admin gets prodded by the system every time this happens - "nomail"ing that address is definitely the right answer.
* Ben Okopnik * Editor-in-Chief, Linux Gazette * https://linuxgazette.net *
Rick Moen [rick at linuxmafia.com]
Thu, 6 Jul 2006 21:57:36 -0700
Quoting Benjamin A. Okopnik (ben at linuxgazette.net):
> On Thu, Jul 06, 2006 at 05:56:55PM -0700, Rick Moen wrote:
> > $ whois barrydonovan.com | more > ^^^^^^^^^^^^^^^^ > Whoops! That should, of course, been "whois barryodonovan.com" (note the > 'o' between the first and the last names):
And that was my error! I must be tired, I guess -- though there are other signs elsewhere that should have warned me. When I spell the domain correctly, I of course get the same "whois" results you do.
One take-away lesson: Copy and paste are your friend. Retyping of crucial data is to be strenuously avoided.