Question

How to disable sendmail listening on port 25

I only use my LAMP based setup to send outbound mail and have another mail server to handle inbound mail.

I wanted to understand (for security reasons) how I could disable sendmail listening on port 25.

I’m running the LAMP image: Ubuntu Sendmail 8.14


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This is exactly what I needed. Thank you!

Hey Jason, <br> <br>You could setup default firewall rules that allow outgoing connections, but not incoming ones. Assuming you need ports 22 and 80 open, it’s as simple as: <br> <br><pre> <br>ufw default deny incoming <br>ufw default allow outgoing <br>ufw allow ssh <br>ufw allow http <br>ufw enable <br></pre> <br> <br>Check out this article for more info on using ufw to setup firewall rules: <br> <br>https://www.digitalocean.com/community/articles/how-to-setup-a-firewall-with-ufw-on-an-ubuntu-and-debian-cloud-server