Installing a Fabric or Forge server lets you run mods that change and expand Minecraft, and adding those mods is mostly a matter of dropping files into the right folder.
Fabric or Forge: which one
Both are modding platforms, and the mods you want decide which you pick. A mod is built for one or the other, so check the mod page before you start.
- Fabric - lightweight and fast to update to new Minecraft versions. Popular for performance mods like Lithium and for lighter modpacks.
- Forge (and its fork NeoForge) - the long-standing platform behind most big content modpacks.
Whichever you choose, every mod on the server must match both the platform and the exact Minecraft version.
Switch your server to Fabric or Forge
The easiest route is the Startup tab, where your server variables live.
- Take a Backups snapshot of your current world.
- Open the Startup tab.
- Change the server type or loader variable to Fabric or Forge, and set the Minecraft version you want.
- Save, then go to Settings and press Reinstall so the panel downloads the correct server files.
- Watch the Console until it finishes loading, then stop the server.
If you would rather install a specific loader build by hand, you can upload the server jar on the Files tab and point the startup jar variable at it.
Add your mods
- Download each mod as a .jar file. Get them from the author's page and match your Minecraft version and loader exactly.
- Open the Files tab and go into the mods folder (it appears after the first Fabric or Forge start).
- Upload every .jar into mods. You can drag several in at once.
- Add any required library mods too. Many Forge mods need a library like an API jar, and the mod page lists these.
- Restart the server and read the Console log to confirm each mod loads.
Client and server must match
Players joining need the same loader and the same mods installed in their own launcher, otherwise they are kicked on connect. Share your mod list, or better, a modpack, so everyone is on identical files.
When something will not start
If the Console shows a crash, read the last error lines. The usual causes are a mod built for the wrong Minecraft version, a mismatched Fabric or Forge build, or a missing library mod. Remove the newest mod you added and restart to find the culprit. Because you took a snapshot first, you can always roll back from the Backups tab.
You can also install a ready-made modpack instead of hand-picking mods. See our modpack install guide for that workflow.
Still stuck? Jump into our Discord at discord.gg/GuavaHost and the team will help you out.