Port 25 is the world wide internet standard for smtp mail servers to listen on for inbound mail. There is no problem of changing your smtp email server to listen on port 24, except for the fact that no body on the internet can reach your smtp email server because they will be sending to port 25 which your ISP has blocked and you are not listening on. So for all practical purposes it does nothing for you.
Last year I read that zoneedit was developing an port 25 redirect as an companion to their port 80 redirect. Check out www.zoneedit.com to see if it's available yet. Besides ISP blocking port 25, port 80 is also blocked for the same reasons. Once you sign up for the free zoneedit service all your domain name driven traffic passes through zoneedit. You can configure your zoneedit account to redirect port 80 to say port 8080 and then config your web server to listen on port 8080 and you bypass your ISP's block. If zoneedit has it's port 25 redirect available it will allow you to do same thing. Check it out and the other free zoneedit like companies out there. One of then may have port 25 redirect working. If you find any please report back to this thread for the archives. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Doug Hardie Sent: Sunday, June 06, 2004 12:29 PM To: Mark Cc: Gerard Seibert; freebsd-questions Subject: Re: Changing SendMail Port Number On Jun 5, 2004, at 17:35, Mark wrote: > Gerard Seibert wrote: > >> This is probably a stupid question, but how do I change the SMTP port >> number that SendMail listens in on? I want to change it to something >> else, like perhaps 24. My ISP is blocking 25 and I want to get around >> that problem. > > And how will clients (the world) find you then, on port 24? > > Besides, are you sure your ISP blocks *incoming* port 25? That is > somewhat > unusual; *outgoing* 25, yes (for dialup users), but incoming? > Regardless, > same difference: you can start sending on port 24, but since the world > is > listening on port 25, that will do you little good. There are ISPs out there that block port 25 to any destination other than their mail server. If you are connected to one of them there is no way to access your ISP's mail server. Thats why we provide support for both ports 25 and 26. I have never seen port 26 blocked. Almost all mail clients provide the ability to change the port it uses. We provide instructions to our users on how to make that change if they need it sl that they can send mail through our server. We do require the use of SMTP-AUTH to avoid an open relay. Blocking port 25 is an attempt to prevent the use of open relays. _______________________________________________ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]" _______________________________________________ [EMAIL PROTECTED] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
