[TAG] [MAILER-DAEMON at localhost.localdomain: Undelivered Mail Returned to Sender]
cssutto at attglobal.net
Wed Aug 16 17:36:35 MSD 2006
I attach a copy of my hosts file for your comments.
Quoting Rick Moen (rick at linuxmafia.com):
> Quoting Claude Sutton (claudesutton at cognisurf.com):
> > I appreciate all of your efforts on my behalf, more than you know,
> > because most of this is totally over my head. I will have to work on it
> > tomorrow. Too late tonight.
> > I have no idea how the "local host" thing got in there. I will have to
> > trace back to see where it is.
> > Postfix came with whatever and I have no idea how to replace it, so that
> > will take time to research.
> > I have no idea what a null mailer is.
> We're with you in all of this, Claude -- though there's a limit to what
> any of us can do at a distance. Believe me, we do sympathise, and
> applaud you as a new Linux user taking on some of the classic
> configuration tasks of the professional system administrator.
> I try to be kind and understanding to new Linux users even when I'm
> tired and cranky -- and at the minimum apologise in advance to such folk
> for any excessive bluntness.
> Your public DNS records claim that your domain's designated recipient
> machines for SMTP e-mail (termed "mail exchangers" or "MXes") are:
> mail.cognisurf.com (1st priority)
> smtp.ipapp.com (2nd priority -- used if the other isn't reachable)
> I'm guessing that the first of those is _your_ Linux box, the one on
> which you have Postfix configured -- and that the second is your ISP,
> IP Applications Canada Corp. of British Columbia.
> Ben noticed, recently, that both MXes refuse mail addressed to
> postmaster at cognisurf.com . If I guessed correctly about you being the
> owner/administrator of "mail.cognisurf.com", then there's a problem
> on your machine _and_ the same problem on your ISP's SMTP host.
> > That has finally sunk in on me. However, until all of this came up, I
> > had no idea because everyone was accepting my emails.
> Well, it's possible -- and you might be able to get by indefinitely not
> accepting mail to that address. (The RFCs also dictate that you must
> accept mail at "abuse at cognisurf.com", and must accept mail _from_ the
> special address "<>" that is used for forwarding mail diagnostics.)
> In any event, unless I've messed up, I've recently made my SMTP host --
> which, by the way is primarily called "linuxmafia.com" but also has a
> secondary identity as "lists.linuxgazette.net" -- categorically accept
> mail prospectively from any sending address in the "cognisurf.com"
> domain, without requring that your domain accept mail at RFC-dictated
> > I thought that when I changed my "from" to attglobal.net that I was
> > being routed through their server and that at that point cognisurf had
> > nothing to do with it.
> If you're having a problem with any particular piece of mail bouncing
> that you addressed to my machine from _anywhere_, please do send a copy
> of the bounce message to me with _full headers_ (command "h" in mutt),
> and I'll be glad to explain it to you.
> Before you ask, you can make your "please explain this bounce" message
> not _itself_ bounce by sending it to "postmaster at linuxmafia.com" or
> "postmaster at lists.linuxgazette.net", which accept all non-forged mail
> (as _likewise_ mandated by the RFCs).
> > Remember, I am dialing in through wireless broadband with Alltel. So
> > I thought that in that case I am using the Alltel system to get out
> > and the attglobal.net system tor replies.
> We cannot comment until we see the full headers of that mail -- but
> definitely can and will, if/when you provide them.
> To answer one of the implied questions above: A "nullrouter" is a
> deliberately simple, small SMTP server (daemon) package -- one just
> smart enough to drop off all outbound SMTP mail at an (e.g.) ISP
> "smarthost" that does all further routing and delivery of that mail.
> The rather odd-sounding name is taken from the first-written example of
> that category.
> One advantage of nullmailers over more-complex, general-purpose SMTP
> mail packages security: With their limited feature set and small,
> more-easily-auditable source code, they typically have either perfect or
> nearly perfect security records.
> Another advantage is extreme ease of setup and administration.
> The drawback is that a nullmailer (by design) isn't very smart or
> capable -- it basically lobs everything at a designated "smarthost",
> which is then Somebody Else's Problem. That's good in the sense that
> it's one thing fewer for you to have to manage; it's bad in the sense
> that you cannot manage how your ISP handles your outbound mail.
> It's almost koan-like: The good news about a full-service Linux box is
> that you do it all yourself. The bad news is the same as the good news.
> As to the other implied question: I'm betting that
> "localhost.localdomain" is something that Postfix picked up from
> /etc/hosts because you there is _not_ a specifically declared hostname
> in Postfix's main.cf
> I'm thinking you'll want to read these two snippets:
> (Sadly, I'm a little out of my depth, here, having never administered or
> configured Postfix.)
> "localhost" is a default machine identity that always exists for any
> machine with a TCP/IP presence. If your machine keeps coming up as
> "localhost" or "localhost.localdomain", then probably you're missing a
> line that ought to be in /etc/hosts. For example, my server's
> /etc/hosts file consists of these contents:
> 127.0.0.1 localhost.localdomain localhost
> 184.108.40.206 linuxmafia.com www.linuxmafia.com uncle-enzo enzo
> 220.127.116.11 cache
> 18.104.22.168 airport airport.deirdre.org #802.11b base stn.
> #22.214.171.124 macaroni macaroni.deirdre.org #not in service
> 126.96.36.199 emperor emperor.deirdre.org
> # printers
> 10.0.1.213 lexx
> # static IPs for installfests
> 10.0.1.5 kenny
> # The historic "kitchen" k6 box has been given away. A replacement may arise.
> 10.0.1.215 kitchen cthulhu cthulhu.linuxmafia.com
> 10.0.1.216 yakko
> 10.0.1.217 wakko
> 10.0.1.218 dot
> # The following lines are desirable for IPv6 capable hosts
> ::1 ip6-localhost ip6-loopback
> fe00::0 ip6-localnet
> ff00::0 ip6-mcastprefix
> ff02::1 ip6-allnodes
> ff02::2 ip6-allrouters
> ff02::3 ip6-allhosts
> Notice the first two lines. The second is my _real_ IP and hostname(s).
-------------- next part --------------
127.0.0.1 localhost.localdomain localhost mythinkpad
# The following lines are desirable for IPv6 capable hosts
::1 ip6-localhost ip6-loopback
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