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Extra port for smtp mail

Scubapro

New Pleskian
How can i add an extra port for smtp mail. The provider of a client is blocking port 25. How can i add port 2525 that i can use for smtp. Port 25 must also be available for other customers.
 
Hi,
Is there a problem with port 587? "Enable Message Submission" in your mail server settings will allow outbound mails to be sent through port 587 (using smtp auth),

Paul.
 
Hi Paul,

Thanks for your reply. Is this option the solutions for my problem? I don't understand what 'Enable Message Submission' means in relation to the port problem.

I enabled it and restarted Postfix but with no result. Outlook says that he can't connect to the smtp server on port 587. Port 25 stays available, so thats good. Any ideas?

Kind regards.
 
Can you telnet the mail server on port 587? As I say he'll need to connect with smtp authentication.

If you can't telnet to it, then check whether postfix is listening : lsof -i tcp:587

If it is then you've probably firewalled everyone out from it, if it isn't then there's a panel problem.

And yes this is a solution to your problem, this is what we use, in fact I'd prefer it if everyone connected through port 587

Paul
 
Hi Paul,

Thanks for your reply. I can't telnet to port 587.

lsof -i tcp:587 says: TCP *:submission (LISTEN)

So probably the firewall is the problem. Now i'm a dummy again. How can i change the firewall to fix this problem.

Thanks Jaap
 
Are you using the Plesk firewall? I'm guessing that either your not (because it would open port 587 alongside port 25) in which case you're going to need to tell us what you're using (plain iptables or something else like APF, CSF etc etc), or its a hardware firewall thats blocking you, in which case you'll need to contact whoever administers the hardware firewall.

Sorry can't really be any more helpful without knowing more information,

Paul.
 
Hi Paul,

In the firewall in Plesk i see that SMTP (submission port) server is on Allow incoming from all. I contacted my hoster by mail and asked him if there is an other firewall in front of Plesk. When i have the answer i will let you know. Thanks!

Jaap
 
Hi Paul,

My hoster opened port 587 on the firewall and now the problem had been solved. Tanks for your time!

Jaap
 
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