Long time before (may be one and half year ) I configure server with ISPConfig and all going fine. Recently we are facing problem in sending & Recieving email on mail.aissworld.com. Few weeks before ISP Block email port they said we are spamming from that port. How ever after a while port open and we able to recieve email but still issue in sending email. Few days before I am even unable to recieve email. Here is message from gmail when sending email. This is an automatically generated Delivery Status Notification THIS IS A WARNING MESSAGE ONLY. YOU DO NOT NEED TO RESEND YOUR MESSAGE. Delivery to the following recipient has been delayed: [email protected] Message will be retried for 2 more day(s) Technical details of temporary failure: The recipient server did not accept our requests to connect. Learn more at http://support.google.com/mail/bin/answer.py?answer=7720 [(10) mail.aissworld.com. [114.34.87.31]:25: Connection timed out] ----- Original message ----- DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:date:message-id:subject:from:to:content-type; bh=cHiHuKLSZgwxoOohmakZKZGnajobgNk8ihO4nQidB5Y=; b=Vx/R5a9GnaUAqbmNRElRPh9QKyzNTTowqGq0w71HCrsjOG8+PM7OjLvXedpitNja7j vqpEqUgOsvQPpQQ/iJDsE/+LCsAx1QLl6Z7YGW1y6XgeTVRZkQ6GKvGBrZIffu0lM6uH 26tC7enjipTuz4ANCX417VnZX6crkDD6PGWj17yTsQ97YbHLhakn6kQUHb/ntz7i9yDA d1ARTrxw8YX6szhOTUR2+FNnhXOY1tVnN65TYb8h7Z+Q3s17tn9+/fCgitlDpmrem2ub g934PcMw+5ie1jORAEtEQEeTyZNAs5/AVoeBIYXUkrtG9gyHPVN40n/MuWuFiIoylKQ9 83mA== MIME-Version: 1.0 Received: by 10.52.28.71 with SMTP id z7mr19971685vdg.105.1342026236679; Wed, 11 Jul 2012 10:03:56 -0700 (PDT) Received: by 10.220.80.8 with HTTP; Wed, 11 Jul 2012 10:03:56 -0700 (PDT) Date: Thu, 12 Jul 2012 01:03:56 +0800 Message-ID: <CAATPF_RYm=KU9nHbOYfvqBRMaozWkHtxYt=rL2t=uNmEZJqgng@mail.gmail.com> Subject: Test Mail From: Piyush Verma <[email protected]> To: [email protected] Content-Type: multipart/alternative; boundary=20cf3078119e1dd5c904c490d5bf Port is still open no idea why so. Please Suggest us solution . Webhosting is not my business but we use it for our internal office use. For us is there any effordable paid service for mentainence of server ? Thanks & Regards Piyush Verma
Seems as if your provider blocks port 25 incoming (from the internet to your server) and gmail rejects the emails for that reason. Many email providers do a check of the sending email server by connecting back to it and if that fails like in your case, the email is rejected. A solution might be to use a external relay server for sending. If your internet access provider offers a smtp server for sending emails, then you might use this server as relay. You can set the relay server in ispconfig under System > server config > mail.
Thanks Till for relay suggestion I will check for that. Currently I am not even able to recieve email. and port is open I jsut tested again now and here is the result below. nmap aissworld.com Starting Nmap 5.21 ( http://nmap.org ) at 2012-07-14 08:57 CST Nmap scan report for aissworld.com (114.34.87.31) Host is up (0.011s latency). rDNS record for 114.34.87.31: 114-34-87-31.HINET-IP.hinet.net Not shown: 983 closed ports PORT STATE SERVICE 21/tcp open ftp 22/tcp open ssh 25/tcp open smtp 53/tcp open domain 80/tcp open http 110/tcp open pop3 143/tcp open imap 443/tcp open https 993/tcp open imaps 995/tcp open pop3s 3306/tcp open mysql 5222/tcp open unknown 7777/tcp open unknown 8080/tcp open http-proxy 8081/tcp open blackice-icecap 9090/tcp open zeus-admin 9091/tcp open unknown Before when port was block result of nmap was different. Do you think it's still blocked by ISP ? Thanks & Regards Piyush Verma
You should ask your ISP. If you run nmap on localhost, you cannot tell if the port is blocked or not.
After lots of fight and time west. Finaly ISP accept that he have blocked the port. And recently opened again. They say that it was spamming form our side from port 25 that's why they block. But I would port 25 is used to recieve emails not send email right ? To send email I just need to establish connection to remote server on port 25 from any local port right ? How ever any possible way to check and solve that this situation not happen agail ? Thanks & Regards Piyush Verma
Port 25 is used for email server communication, it can be used to send emails and to receive emails. If your server was blocked for spamming, they should have blocked only port 25 outgoing but it seems that they blocked it in both directions in your case.
Dear Till, Thanks for information. Now the port is open my side but next big question is how to test and prevent spamming. Is there any predefined checklist or tutorial which I could follow ? Thanks & Regards Piyush Verma
I think Any program running in host can open port 22 and start sending email like sendmail or may be some other jave based socket program. if some how we could restrict that only postfix have rights to open outgoing port 25.......... Humm. I know a bit socket programming in that we only specify destination ip and port how blocking local port 25 can prevent stablising connection to xIP:25 port ? But when I block port 25 outgoing postfix was not able to send mail out it's mistry for me. Any suggestion ?
