ok, so heres the problem... i ha

[dwbizzle]

ok, so heres the problem...

i have a mail server that hosts somewhere between 40 or 50 *virtual* domains.

the server has absolutley no problems sending mail to any domains *other* than mindspring.com

now, whats weird is that earthlink.net mail is delivered without a hitch.. its the same mail server.

I have contacted the abuse department of corporate earthlink and worked with a guy there for about an hour.

the messages leave my server, but dont' arrive at mindspring, and aren't sent back to my server.

its like they just disappear to /dev/null er something.

so we have come to the conclusion that its has to be a configuration problem. but my question is; why would it work for almost a year and a half and then stop...

my server isnt being blacklisted, it can connect to mindsprings server w/ telnet, their spam software isn't blocking it.

i don't have a clue,

oh and my boss is being a major dick about it because his wife can't email her "friend" at mindspring. bfd...

_______________
dwb

 

[sdeakin]

First thing I would do is monitor the network connection between you and the mindspring.com mail server.

doing a nslookup and reverse resolve, it would appear that the mindspring mail servers are on the 207.69.200.0 subnet, so try the following and send some mail

# tcpdump eth0 net 207.69.200

BTW I am assuming eth0 is the network card the e-mails will originate from.

Scotty

 

[aixmurderer]

Well, if you can connect via telnet to port 25, and the mail has goes from your server then it's safe to say the problem isn't at your end.
Their server relied with all the handshaking involved to satify your mail server that it was accepted OK.
They need to look at their MTA settings for the mindsping virtual domain, the problem must lie there.

You can test it manually, look here for a how-to:

http://support.im1.net/privateserver/Manually_Checking_Services.htm

IBM Certified Confused - MQSeries
IBM Certified Flabbergasted - AIX 5 pSeries System Administration
MS Certified Windblows Rebooter

 

[dwbizzle]

the messages do leave my server, but according to the tech i spoke with on the phone, his servers never see it.

if i try to connect to mindspring via telnet and manually try to send a message, i get a relaying denied error and can't send the message. It doesn't see my ip address as an earthlink address. Which is right, otherwise they would be an open relay.

of course earthlink says its a configuration problem on my end, but the more i look into it the more i just dont' see it being my problem.

smtp is kinda like a refridgerator, if everythings cold you know its working.

 

[sdeakin]

are you using sendmail? if so, do a 'mailq' from the command line and see if it's queuing mail on your server. If so, then the 'relay denied' message you got on the manual test is why no mail gets through.


Can I ask what the from and to domains are i.e.

from someone@earthlink.net to someone@mindspring.com ? Depending on how the mindspring relays are configured could affect the way it relays mail - i.e. if you pretend you are from earthlink.net, but your ip address does not resolve to an earthlink address (which appears to be the case) then the relay may think you are spoofing and reject the e-mail.

How does you MTA announce itself during the HELO or EHLO step? And what does the server think it really is!

Scotty

 

[dwbizzle]

my server annouces its self as mail.mycompany.net.

which is right.. and earthlinks server resolve that to the appropriate address.

the domains are from any of my 50 er so virtual domains, the one i'm using is someone@usrlocal.net trying to get to someone@mindspring.com....

yes, their server do a reverse lookup on the dns and see i'm not connecting from an earthlink connection..

my server is queuing the mail, however, sometimes it goes and sometimes it doesn't. most of the time though it just queues it up.

 

[aixmurderer]

Is there an MX record entry for your "userlocal.net" domain which points to your mail server IP? If it points somewhere else you will need to get it changed. That one possible cause of your problem.

IBM Certified Confused - MQSeries
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[dwbizzle]

its qmail, forgot to mention that.

usrlocal.net points to my mail server, i host the DNS servers as well...

the servers can communicate fine.. i just don't get why i can recieve mail but not send it to mindspring.com.

i'm loosing my hair.

 

[azimuth0]

It seems to me that the problem is on their end. The crucial bit of evidence is that their mailserver considers your test email to be relaying. It should ONLY consider that if the email address of the recipient is different from the hostname Naturally, it would only deny the relaying if the sender wasn't within the earthlink domain (using them as an ISP, for instance)

I suspect that they misconfigured their server, and it regards all outside email sent to mindspring.com as being suspect. It would also explain why it broke even though you didn't change anything.

http://www.sanctuary.org/~azimuth/

 

[dwbizzle]

ok, so here is where i'm at..

[root@mail root]# telnet mail.mindspring.com 25
Trying 207.69.200.226...
Connected to mail.mindspring.com.
Escape character is '^]'.
220-blount.mail.mindspring.net ESMTP Exim 3.33 #1 Mon, 29 Sep 2003 09:12:27 -0400
220-NO UCE. EarthLink does not authorize the use of its computers or network
220 equipment to deliver, accept, transmit, or distribute unsolicited e-mail.
helo
250 blount.mail.mindspring.net Hello mail.compunet1.net [206.96.244.7]
mail from:xxx@usrlocal.net
250 <xxx@usrlocal.net> is syntactically correct
rcpt to:xxx@mindspring.com
550 relaying to <xxx@mindspring.com> prohibited by administrator

hmmm... now thats not right...

when mailed from the exchange server using outlook xp the messages arrives at its sender without a problem...

yet, when you telnet and change the from address..ie

mail from:xxx@compunet1.com
250 <xxx@compunet1.com> is syntactically correct
rcpt to:xxx@mindspring.com
550 relaying to <xxx@mindspring.com> prohibited by administrator

so the question arrises... is it completely their problem? or only partially? how do you convience a multi-million dollar company they have a problem with their mail server? and how do you convience your boss that its not your equipment?


oh, and just for fun, i got an email from a customer saying that their internet wasn't working... got an email... hmm.

 

[dwbizzle]

oh and if i telnet from the exchange server that sent the message fine through outlook....

Trying 207.69.200.226...
Connected to mail.mindspring.com.
Escape character is '^]'.
220-blount.mail.mindspring.net ESMTP Exim 3.33 #1 Mon, 29 Sep 2003 09:12:27 -0400
220-NO UCE. EarthLink does not authorize the use of its computers or network
220 equipment to deliver, accept, transmit, or distribute unsolicited e-mail.
helo
250 blount.mail.mindspring.net Hello mail.compunet1.com [206.96.244.7]
mail from:xxx@compunet1.com
250 <xxx@compunet1.com> is syntactically correct
rcpt to:xxx@mindspring.com
550 relaying to <xxx@mindspring.com> prohibited by administrator

 

[marsd]

It's a misconfiguration on their end.
There may be an access restriction against
that particular address from your domain,
or it may be that there is a dns problem and
they are using very strict anti-UCE relay
rules.

Using postfix in a very strict anti-UCE
environment with the requirement that client
hosts names must resolve I soon found that
this type of precaution becomes unworkable.

Let us know how it turns out.

 

[dwbizzle]

get this! it works today! AHHHHH!!! i haven't changed anything on my end, however, the telnet/smtp error messages that i was recieving on friday are different from the messages i was recieving today... I dunno. I still don't have an &quot;answer&quot; to give to my boss, but i imagine that i could come up with something. Anyways, thanks for the help guys! Hopefully it will work for another year!

 

[lullysing]

It might have been a MTU problem between you and the other mail servers. When weird things like this happen, start trying to ping with weird MTUs with the non fragmentation bit set to your pings and see if it goes thru.

The phenomenon is called a &quot;blackhole router&quot;. We currently have a customer having a similar problem. The problem with this kind of thing is that sometimes it's not even the ISPs fault, but saaayy... a defective card somewhere @ the telco.

There is a cute article about this in microsoft's knowledgebase that a customer linked me to the other day... *scuffles* yeah, knowledgebase #159211 : diagnose and treatment of black hole routers.

 

[dwbizzle]

yea i could see that affecting things rather oddly!

so any ideas on how to explain this to a non-computer-literate boss??

thanks again for the help!

 

[aixmurderer]

>> so any ideas on how to explain this to a non-computer-literate boss??


Let's not even go there... It's like trying to resurrect the dead.

IBM Certified Confused - MQSeries
IBM Certified Flabbergasted - AIX 5 pSeries System Administration
MS Certified Windblows Rebooter

 

[lullysing]

Ask the people you dealt with if they touched ANYTHING. then start from there.