Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

First I try to explain my server environment.

I have two virtual servers, the host server is Ubuntu. The mailserver is Debian Squeeze installed with this tutorial: http://workaround.org/ispmail/squeeze.
Everything works nicely.

There is just one big mysterium which causes me hard work. I can not connect from my mail server to the mail server "mail.swisscom.com". My mail server is "mail.pixelwolf.ch". From the mail server of Swisscom I can not receive or send emails to my server (pixelwolf). From my server to Swisscom I can not receive or send messages.

Ok I tried the following things:

  1. DNS Check (OK, DNS can be resolved)
  2. Routing (OK, traceroute and mtr shows the correct routing)
  3. Sending/Receiving mails from others (OK, tested from 3 different mail servers)
  4. Telnet to mail.swisscom.com (NOT OK, there is a Connection timeout)

TCPdump shows the connection to mail.swisscom.com but no connection from Swisscom to Pixelwolf. On the exchange account of Swisscom there is a delay message and after 12 hours there is a "undeliverable" message. It says pixelwolf.ch has permanent fatal errors. On my side my mail server said there is a connection timeout and Postfix tries to deliver the mail in the next 5 days.

The first problem showed up yesterday at 3pm. The server is unmanaged and I even tried to resolve the problems with the hosting center hetzner.de and they said there is no error on their side. Swisscom said they can't look at the problem because the company is much too big (over 20000 employees).

So what can I do? My boss can't send me mails and I can't send him mails.

UPDATE: My server is not blacklisted on any spam blacklist like Spamhaus or Spamcop.

share|improve this question
    
It's possible that Swisscom is blocking your server at the TCP connection level. You could try contacting the Postmaster at Swisscom, or PM me and I'll make a personal introduction to him. –  Ken Simpson May 18 '12 at 19:12
    
First you can't PM on stackexchange and second the problem is solved. I don't know what they did but they told me they can't do anything. In such a big company you as one person are nobody. So it's impossible to resolve such problems for the future. –  thonixx May 27 '12 at 0:11
    
Oops - yes sorry, PMing is impossible on StackExch. Glad the problem is now fixed. –  Ken Simpson May 30 '12 at 15:28
add comment

1 Answer 1

I can not connect from my mail server to the mail server "mail.swisscom.com".

Please provide details on what cannot connect, and relevant postfix logs of connection attempts if you have these.

My mail server is "mail.pixelwolf.ch". From the mail server of Swisscom I can not receive or send emails to my server (pixelwolf).

Please provide relevant postfix logs of delivery attempts of both these cases.

From my server to Swisscom I can not receive or send messages.

Please provide relevant postfix logs of delivery attempts of both these cases.

share|improve this answer
    
1: telnet to mail.swisscom.com on port 25 fails with Connection timeout (and on every redundancy ip too). there ist just port 25 open on mail.swisscom.com 2: postfix log just says connection timeout, no more message provided. log file here: fixee.org/paste/v59js4m 3: from the other side (swisscom) i cant provide any logs or test cases. swisscom is a big company with almost 20000 employees. so this is really impossible. –  thonixx Apr 23 '12 at 9:47
    
BTW swisscom even doesnt try to connect to my server. if i send a mail there is no connection from swisscom to my server (tested with tcpdump) BTW2 from the same ip but another operating system there is the same connection timeout. so its not the problem of my configuration. –  thonixx Apr 23 '12 at 9:52
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.