Redirecting SMTP
Due to my new appartement I have a new ISP, like all of them reroutes every connection on port 25 to it’s own smtp server. This is fine if you use their e-mail service but not if you are a domain owner or small company that just wants to use it’s own mail server. Today I fixed this issue in 10 minutes using rinetd on a server of mine, it redirects tcp traffic from one port to another, bypassing port 25 until I’m past my isp network.
The setup is quite simple:
- apt-get install rinetd
- note down, server ip and destination ip(mail server)
- add your redirect line according to format
- restart rinetd
- all, done.
This is of course if you are running ubuntu or debian on your server, but for other distros it should be almost as simple.