13 Replies Latest reply: Jul 1, 2013 11:28 PM by Alfista_SK
Alfista_SK Level 1 Level 1 (0 points)

Hi,

 

I have for about 3 mounts instaled Mountain Lion server and all was working OK, but some days ago I don't have become mails. I can send to all addresses, I can become mails send from my server, but when some one outside my server sent me an email, I don't become it. I have tested it and I found that some mails are come to me, but not all.

A friend tell me that can be authentication reverse DNS recors of incoming mails, but I don't found anything about it and in posix mail seting too.

Please can you help me and tell me what can be, that I can repair it.


OS X Server
  • 1. Re: Problems with incoming mails...
    JaimeMagiera Level 2 Level 2 (305 points)

    Please provide example mail logs from an incoming message (/var/log/mail.log)

  • 2. Re: Problems with incoming mails...
    MrHoffman Level 6 Level 6 (12,455 points)

    Post your (public) domain, and we'll check the MX record and related DNS details.  If you don't want to do that, there are DNS verification services around that can reportedly check your mail server DNS, or you can follow the sequence from this or this or other related threads.

  • 3. Re: Problems with incoming mails...
    Alfista_SK Level 1 Level 1 (0 points)

    Hi,

     

    the log is on: http://pastebin.com/bkx4QXnH

    In the log are more days ago too and the problem is from about 24. or 25. june to today. You can see all.

    The domain is: prostudio.sk, mail server is: mail.prostudio.sk.

    I thing it isn't in the domain, while it was working corectly some months.

  • 4. Re: Problems with incoming mails...
    JaimeMagiera Level 2 Level 2 (305 points)

    In particular, I'm asking you send an excerpt from the logs from the exact time that you sent a message - and provide the "from" and "to" address of that failing message. We don't want to have to go through a week of logs line-by-line.

  • 5. Re: Problems with incoming mails...
    Alfista_SK Level 1 Level 1 (0 points)

    Sorry here you have the exact log part from sending an mail to my server.

     

    1. Jun 28 08:11:37 server1.prostudio.sk postfix/smtpd[15875]: warning: hostname suska.router-3.tvbox.sk does not resolve to address 77.247.225.215: nodename nor servname provided, or not known
    2. Jun 28 08:11:37 server1.prostudio.sk postfix/smtpd[15878]: warning: hostname suska.router-3.tvbox.sk does not resolve to address 77.247.225.215: nodename nor servname provided, or not known
    3. Jun 28 08:11:37 server1.prostudio.sk postfix/smtpd[15875]: connect from unknown[77.247.225.215]
    4. Jun 28 08:11:37 server1.prostudio.sk postfix/smtpd[15878]: connect from unknown[77.247.225.215]
    5. Jun 28 08:11:37 server1.prostudio.sk postfix/smtpd[15880]: warning: hostname suska.router-3.tvbox.sk does not resolve to address 77.247.225.215: nodename nor servname provided, or not known
    6. Jun 28 08:11:37 server1.prostudio.sk postfix/smtpd[15880]: connect from unknown[77.247.225.215]
    7. Jun 28 08:11:37 server1.prostudio.sk postfix/smtpd[15883]: warning: hostname suska.router-3.tvbox.sk does not resolve to address 77.247.225.215: nodename nor servname provided, or not known
    8. Jun 28 08:11:37 server1.prostudio.sk postfix/smtpd[15883]: connect from unknown[77.247.225.215]
    9. Jun 28 08:11:37 server1.prostudio.sk postfix/smtpd[15885]: warning: hostname suska.router-3.tvbox.sk does not resolve to address 77.247.225.215: nodename nor servname provided, or not known
    10. Jun 28 08:11:37 server1.prostudio.sk postfix/smtpd[15885]: connect from unknown[77.247.225.215]
    11. Jun 28 08:11:38 server1.prostudio.sk postfix/smtpd[15880]: disconnect from unknown[77.247.225.215]
    12. Jun 28 08:11:38 server1.prostudio.sk postfix/smtpd[15883]: disconnect from unknown[77.247.225.215]
    13. Jun 28 08:11:38 server1.prostudio.sk postfix/smtpd[15878]: disconnect from unknown[77.247.225.215]
    14. Jun 28 08:11:38 server1.prostudio.sk postfix/smtpd[15885]: disconnect from unknown[77.247.225.215]
    15. Jun 28 08:11:38 server1.prostudio.sk postfix/smtpd[15875]: disconnect from unknown[77.247.225.215]
    16. Jun 28 08:14:58 server1.prostudio.sk postfix/anvil[15882]: statistics: max connection rate 5/60s for (submission:77.247.225.215) at Jun 28 08:11:37
    17. Jun 28 08:14:58 server1.prostudio.sk postfix/anvil[15882]: statistics: max connection count 5 for (submission:77.247.225.215) at Jun 28 08:11:37
    18. Jun 28 08:14:58 server1.prostudio.sk postfix/anvil[15882]: statistics: max cache size 1 at Jun 28 08:11:37
  • 6. Re: Problems with incoming mails...
    JaimeMagiera Level 2 Level 2 (305 points)

    Is 77.247.225.215 the IP of the machine you are sending messages from? suska.router-3.tvbox.sk does not resolve forward. It does resolve reverse however. Something is misconfigured there.

     

    jaimelm$ host suska.router-3.tvbox.sk

    Host suska.router-3.tvbox.sk not found: 3(NXDOMAIN)

     

    jaimelm$ host 77.247.225.215

    215.225.247.77.in-addr.arpa domain name pointer suska.router-3.tvbox.sk.

     

    What DNS servers is your OS X Server configured to use? Note that the related parameters in Postfix are called helo_restrictions. In particular, the values reject_invalid_hostname and reject_unknown_hostname. I wouldn't disable those however. I'd fix your DNS. 

  • 7. Re: Problems with incoming mails...
    Alfista_SK Level 1 Level 1 (0 points)

    my is prostudio.sk (82.119.123.106) but to this monday it was all ok and I have configured my own DNS and transfer is on my provider 195.28.64.99 and 195.80.171.4.

    I don't change anything from install for about 4 mounts.

  • 8. Re: Problems with incoming mails...
    MrHoffman Level 6 Level 6 (12,455 points)

    Whether or not you changed it, the mail server public DNS is incorrectly configured.  The reverse translation does not match the forward translation:

     

    $ dig +short MX prostudio.sk

    10 mail.prostudio.sk.

    $ dig +short mail.prostudio.sk

    82.119.123.106

    $ dig +short -x 82.119.123.106

    prostudio.sk.

    $

     

    The ISP with the DNS server for 82.119.123.106 needs to change the response to mail.prostudio.sk.

  • 9. Re: Problems with incoming mails...
    Alfista_SK Level 1 Level 1 (0 points)

    Hi,

     

    I have give to recheck it and add the reverse record for mail.prostudio.sk, but at the beginning don't have any reverse records and all was working OK, then I added reverse record only for the domain and all was working some mounth OK, but oknow, I don't do anything on server, I can't become mail from many servers. I found, that I become mails from servers, but with a long delay.

    Have you any idea, what it can do?

     

    Thanks.

  • 10. Re: Problems with incoming mails...
    MrHoffman Level 6 Level 6 (12,455 points)

    Here is why you want to fix your DNS...

     

    When your public DNS configuration is incorrect, other DNS servers can decide that you're probably a spam engine, and drop your outbound mail — which you won't get notified on — and can potentially drop mail aimed for your server — which you won't get notified on.  In these cases, you will not see any indication of any errors, other than eventually hearing about some dropped mail messages from folks that were trying to communicate with you.

     

    Again, some mail will get routed to you and received from you by mail servers with more tolerant settings, which means things will appear fine.  You can enable similar checks in your own mail server, as various folks do.  But again, this has absolutely nothing to do with your mail server — which may be working just fine for most mail — this is how other mail servers perceive your server, based on your DNS.

     

    In short: fix the DNS.


    There will be a delay in arriving mail as the anti-spam greylisting learns the servers you communicate with.  Greylisting can be disabled, but that does mean more spam; greylisting does slow messages, but does not normally cause the loss of any messages among properly-functioning mail servers.  Once your mail server communicates a number of times with the particular remote mail server, the greylisting will be automatically bypassed.  (This training can be a little longer with a few services such as gmail, as Google has a number of mail servers greylisting will learn about.)  When this greylisting case is arising for a particular case, you'll see your mail server returning 450 try again later status to arriving mail from "strange" mail servers, and you can see other servers sending the 450 to you.

     

    That suska.router-3.tvbox.sk address has valid reverse DNS (address to name) but lacks a forward DNS translation; that doesn't look to be a valid mail server, given the DNS errors with it.  While that could be a spam engine, those usually don't have valid reverse DNS.  It is possible to override the anti-spam and related checks for specific hosts, if you don't have control over the DNS translations for the hosts, and if the translations are invalid.

     

    Obviously, the most expedient approach here would be to outsource your mail service to a provider; to have your domain and email hosted.  Make all of this somebody else's problem.

  • 11. Re: Problems with incoming mails...
    Alfista_SK Level 1 Level 1 (0 points)

    Thanks,

    I give to repair the DNS recods. I hope that helps, while I have checked the spam house servers and I'm not there and from that server I'm sending me mails about a half year. It's in office where I work too and no one has problems with it.

    I thing there will be another problem too in the settings, while I don't understand while it won't work after some months ...

    And I have disabled the graylists.

    And I have today become a return mails that sending fails.

     

    The mail system


    <alfista@prostudio.sk>: connect to mail.prostudio.sk[82.119.123.106]:25:   Connection refused

    Reporting-MTA: dns; mail.sunteq.sk

    X-Postfix-Queue-ID: 1568510BB55

    X-Postfix-Sender: rfc822; peter.danko@sunteq.sk

    Arrival-Date: Wed, 26 Jun 2013 12:30:13 +0200 (CEST)


    Final-Recipient: rfc822; alfista@prostudio.sk

    Original-Recipient: rfc822;alfista@prostudio.sk

    Action: failed

    Status: 4.4.1

    Diagnostic-Code: X-Postfix; connect to mail.prostudio.sk[82.119.123.106]:25:   Connection refused

    Received: from localhost (localhost.localdomain [127.0.0.1])

     

    Have you another idea?

  • 12. Re: Problems with incoming mails...
    MrHoffman Level 6 Level 6 (12,455 points)

    It appears that TCP port 25 might be blocked at or before your mail server; either at your OS X Server firewall, at your network firewall, or at your ISP firewall.

  • 13. Re: Problems with incoming mails...
    Alfista_SK Level 1 Level 1 (0 points)

    You mean that can be while I have blocket TCP port 25? I have block it, while I found on web, when I will use SASL authentication and won't be on SPAM Houses it's needed to close this port and I use SSL, so I use other ports.