My server is sending spam

[cryptotheslow]

If they have blocked inbound port 25 connections to you - then yes, that would explain it.

Not very helpful as it means you can't test your new configuration properly

This may not be helping either:

smtpd_client_restrictions = permit_mynetworks, reject

That means only clients in the 79.161.88.51/24, 127.0.0.1/8 ranges can use the server to send. Is that what you need?

[AvengerX9]

hmmm. I need to give them a call and open it up again. I will post back here once its open

[cryptotheslow]

If they are being awkward about opening it up again, you could suggest that you run postfix on an alternative port temporarily whilst you make sure the config is secure.

e.g. you could run the postfix SMTP service on port 25250 and use telnet to make sure it is not acting as an open relay. Once you are happy with that, put it back on port 25 and make sure it will still correctly receive mail for your domain and allow sending by your expected clients.

Moving it off port 25 will pretty much stop any spammers from finding and using it whilst you test.

[AvengerX9]

How would I go about temporary moving it to another port ?

[cryptotheslow]

In file /etc/postfix/master.cf

Comment out or change this line:

smtp    inet    n       -       -       -       -       smtpd -o

to

25250    inet    n       -       -       -       -       smtpd -o

Restart postfix and smtpd should now be listening on port 25250

[dcstar]

Update

# See /usr/share/postfix/main.cf.dist for a commented, more complete version
.........
mynetworks = 79.161.88.51/24, 127.0.0.1/8
.........

If your server is directly connected to the Internet with a valid External IP address then that is (almost) valid, if your server is behind a NAT Firewall with Port Forwarding then that should be the Internal IP range.

I also seriously doubt that are using 255 IP addresses in that range.

[lisati]

Thread moved to Server Platforms.

[AvengerX9]

I tried that, but I get connection refused. Do I have to add it into my iptables too ?

http://mxtoolbox.com/SuperTool.aspx?...truckstop24.no

[SeijiSensei]

May I ask a broader question? Who uses this server? Are you supporting multiple domains and multiple clients, or just one domain? I'm not a Postfix user, but I'm certain there is a way to configure it to accept only mail intended for your domain and reject everything else. That's what you want to have. Mail for you@example.com is accepted and mail for someone@somewhere.com is rejected.

[AvengerX9]

I just need my website to send out mail and to receive mails for that domain.

I have one website hosted there and I'm the only user