CRON and EMAIL

[jechilt]

Once again, I can't figure out the best place to make this post since it involves the cron and the email message generated.

We have a cron that runs nightly. The cron spits out an email and sends from the admin account to the domain administrator email account (two seperate accounts). I have a foward rule on the admin account to a colleage of mine.
We are getting the message rejected because the admin email account is getting NS tacked on. Is there an easy fix for this?

  [email][email protected][/email]
    (ultimately generated from [email][email protected][/email])
    SMTP error from remote mailer after RCPT TO:<[email protected]>:
    host domain.com [xxx.xxx.xxx.xxx]: 550-Verification failed for <[email protected]>
    550-unrouteable mail domain "ns.2dads.com"
    550 Sender verify failed

------ This is a copy of the message, including all the headers. ------

Return-path: <[email protected]>
Received: from admin by ns.2dads.com with local (Exim 4.24)
id 1CHeIj-00084j-O9
for [email][email protected][/email]; Wed, 13 Oct 2004 04:16:01 -0400
To: [email][email protected][/email]
Subject: Nightly Invoice Cron Report
Wrom: ARHDMNNSKVFVWRKJVZCMHVIBGDADRZFSQHYUCD
Message-Id: <[email protected]>
Sender:  <[email protected]>
Date: Wed, 13 Oct 2004 04:16:01 -0400

thanks in advance for any help

 

[fusionictnl]

Reverse lookup set on ? This will cause exim to do a reverse lookup to check if the sender is who he says he is. Looks like you're ns.2dads.com ip: 208.254.3.160 is not reverse lookupable to ns.2dads.com, but to: uu-3-160.buydomains.com.

This will cause exim to reject the mails, because the sender says he is ns.2dads.com. But if he looksup the server it says he is: uu-3-160.buydomains.com. You can't send mails to my server with this configuration, it will alse deny them.

 

[nobaloney]

Once again, I can't figure out the best place to make this post since it involves the cron and the email message generated.

The error you're getting is an email error so this would best be placed as an email problem.

But here will do .

Who is sending you the error? Your mail server or your colleague's email server?

The server sending you the email is attempting to verify the sender [email protected].

My guess is that you're running the cronjob as admin and that your server name is ns.2dads.com. However I could be wrong if your cron job is setting the sender.

The foreign server (your colleague's email server) shouldn't try to very anything except that it can connect to a mailserver at ns.2dads.com. It shouldn't try to find out if there's an actual sender at that address. But when I try to connect to the mailserver at ns.2dads.com, I can't connect, so that's probably the reason for the error.

While fusionictnl is correct in his first paragraph, he's incorrect in his second paragraph unless you've changed exim.conf; the standard exim.conf files produced by exim.org, by DA originally, and by me (the one DA uses now) only check according to RFC protocol; they check to make sure there is a reverse record but not what it resolves to.

The reason is quite simple; machines may identify with multiple names, and reverse IP, even when you set it up for all the names the machine may identify as, will either return the first name, or all of them in an arbitrary but undefinable order, or some subset of them.

So any machine that attempts to get an exact match won't accept legit email in many cases, including almost all cases when an end user tries to send outgoing email through the server.

For example, when I send outgoing email through my server (which I do all the time), my local desktop identifies itself as of1.nobaloney.net, but my reverse dns, set by my adsl provider, is:

adsl-67-112-189-217.dsl.lsan03.pacbell.net

Here's the complete log line showing what I mean; only the email addresses have been changed (below is one line in the log; it may be wrapped below):

2004-10-15 10:55:27 1CIWIY-0007y8-U0 <= [email protected] H=adsl-67-112-189-217.dsl.lsan03.pacbell.net (of1.nobaloney.net) [67.112.189.217] P=esmtp S=788 [email protected] T="subject" from <[email protected]> for [email protected]

Note that of1.nobaloney.net doesn't have to exist in DNS, and it doesn't, because it's a private machine on a private non-routable network. But the domain in the return address must address, and must have a working mailserver.

Jeff