> -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Noel Jones > Sent: 13 October 2008 15:51 > To: postfix users list > Subject: Re: Postfix listening on 25, unable to telnet to 25 > - my first config > > Paul Cocker wrote: > >> -----Original Message----- > >> From: Noel Jones [mailto:[EMAIL PROTECTED] > >> Sent: 13 October 2008 13:36 > >> To: Paul Cocker; postfix-users@postfix.org > >> Subject: Re: Postfix listening on 25, unable to telnet to 25 > >> - my first config > >> > >> Paul Cocker wrote: > >>> All my telneting had been by IP address, the name wasn't > in DNS yet. > >>> I've added it, but I get the same problems. As noted in > my previous > >>> post I've now found I can access the port from the > postfix machine, > >>> just not other machines. > >>> > >> Use netstat or lsof to see if postfix is really listening on the > >> external interfaces. > > > > Netstat reveala > > > > Proto Recv-Q Send-Q Local Address Foreign Address > > State > > tcp 0 0 *:smtp *:* > > LISTEN > > > > Which I believe indicates it is listening on port 25 for > connections > > from anywhere, yes? > > > >> If postfix doesn't appear to be listening on the external > interfaces, > >> check your master.cf. Some distributions of postfix > change master.cf > >> to force postfix to listen on localhost only. > >> Look for a line in master.cf beginning like: > >> 127.0.0.1:smtp inet ... > >> and remove the "127.0.0.1:" part. > >> If this fixes the problem, complain to your distributor. > >> > > > > The smtp line look correct: > > > > smtp inet n - n - - smtpd > > > > Good. Looks as if postfix is ready for connections. > This means your problem is not with postfix, but with > something else interfering with the connection. > > >> If postfix does appear to be listening on external > interfaces, then > >> you have firewall software on that host interfering with postfix. > >> > > > > Definitely nothing in between, of that I'm certain. > >
I should note that, on this front, I can telnet from the same box to our Exchange server on port 25, which operates within the same IP range as the postfix box. Perhaps this hints that I should be looking at the receiving end of the connection? > > Are there any tools which will give me more information > about attempts > > to connect to a port on a remote host? > > See http://www.postfix.org/DEBUG_README.html#sniffer > Run tcpdump on the postfix box to see incoming connections. > Run tcpdump on some external box to see an outgoing > connection to the postfix box (If it's a windows box, use > http://www.wireshark.org). (if it's a windows box, > temporarily disable the antivirus software and the windows firewall) > > -- > Noel Jones > TNT Post is the trading name for TNT Post UK Ltd (company number: 04417047), TNT Post (Doordrop Media) Ltd (00613278), TNT Post Scotland Ltd (05695897), TNT Post North Ltd (05701709), TNT Post South West Ltd (05983401), TNT Post Midlands Limited (6458167)and TNT Post London Limited (6493826). Emma's Diary and Lifecycle are trading names for Lifecycle Marketing (Mother and Baby) Ltd (02556692). All companies are registered in England and Wales; registered address: 1 Globeside Business Park, Fieldhouse Lane, Marlow, Buckinghamshire, SL7 1HY.
