Master server
A master server is a domain that all other game servers (slave servers) call out to, which then get listed in the game's server browser. A game server must list a master server in its server.cfg file in order to be listed in the master server's list.
Jedi Academy and Jedi Outcast shipped with a default master server run by Raven Software. Since launch of both games, it has run into a lot of downtime over the years due to attacks and poor infrastructure.
In the last decade, there have been efforts made in the community to provide secondary and backup master servers in order to keep the game's server list accessible through clients like OpenJK and JK2MV.
How to set your server's master
To indicate what master servers your game server points to is as simple as editing your server.cfg file and add these lines below. As of 2023, these are the recommended servers to use, to make sure it is listed everywhere that people may see.
set sv_master1 "masterjk3.ravensoft.com" set sv_master2 "master.jkhub.org" set sv_master3 "master.ouned.de"
Web server browser
There are a couple web pages that serve as a backup server browser. You can find those at the links below.