What is a Port?

In networking, a port is a communication endpoint. A port is normally tied to a specific process on your computer or server. It allows you to distinguise different kinds of traffic to a specific address. You can kind of see it like letters send to a specific person in a household: in networking different ports are for a specific application or service.

Ports allow for very efficient networking. You can have e-mail, webbrowsing and P2P networking all at the same time, because of ports. There are some common conventions for ports, such as for webbrowsing, file transfers and e-mail.

Commonly Used Ports

Some ports are reserved for common uses. They are part of the backbone of the internet and as a self-hoster, you should know about them:

Port number Used for
22 SSH: Secure shell. When you connect to your server via the Terminal, you probably will use this.
53 DNS: Domain Name Server. Translates your address to an IP address the computer understands.
80 HTTP: Hypertext Transfer Protocol: Used for webpages over an insecure connections.
443 HTTPS: Same a HTTP, but with a secure connection.

Default port for some common self hosted applications

Here you can find the default ports for some of the most used self hosted applications.

Port number Used for
8686 Lidarr: Music collection manager
7878 Radarr: Movie collection manager
8989 Sonarr: Series collection manager
9117 Jackett: ‘Proxy’ for trackers for commonly used collection managers
8181 Tautulli: Plex monitoring software
3579 Ombi: Media request tool
32400 Plex: Media server
9091 Transmission: Bittorrent client
443 Nextcloud: Groupware application suite
8112 Deluge: Bittorrent client