How to Install Modpacks on Your Minecraft Server

Modpacks transform Minecraft into an entirely different game — tech, magic, exploration, skyblock, and everything in between. This guide explains how mods and modpacks differ from plugins, how to install popular packs on your Wasabi Hosting server, and how to size your server’s RAM correctly.

Mods vs. Modpacks vs. Plugins

	Mods	Modpacks	Plugins
What it is	A single game modification	A curated bundle of many mods + configs	A server-side extension
Runs on	Forge / NeoForge / Fabric	Forge / NeoForge / Fabric	Paper / Spigot / Purpur
Client needs it too?	Yes (for most mods)	Yes — the matching pack	No — vanilla clients can join
Examples	Create, JEI, Sodium	All the Mods 9, FTB Skies, Prominence II	EssentialsX, LuckPerms

If you want players to join with an unmodified client, you want plugins instead. Mods and plugins generally cannot run on the same server software.

Mod Loaders

Every modpack is built for a specific mod loader:

Forge — the classic loader; most large packs up to 1.20 use it.
NeoForge — the community continuation of Forge; most modern packs (1.20.4+) use it.
Fabric — lightweight and fast-updating; used by packs like Prominence II and many performance-focused packs.

The modpack’s page (on CurseForge, FTB, or Modrinth) always states the loader and Minecraft version it needs. Your server must use exactly that combination.

Before You Start: Take a Backup

Installing a modpack usually replaces your server files and generates a new world. Create a backup from the panel’s Backups tab first so you can restore your current setup at any time. See Backups.

Installing a Modpack

Via the Panel Installer
Manual Server Pack Upload

The fastest route when your pack is available in the panel:

Open the Version Changer

In the Game Panel, open your server and go to the Version Changer.

Pick your loader or pack

Select the modpack directly if it’s listed, or install the matching Forge / NeoForge / Fabric version the pack requires.

Install and start

Run the install (enable the wipe option if you’re replacing an old setup), then start the server. The first boot of a large pack can take several minutes.

Works for any pack that publishes a server pack (most CurseForge and FTB packs do):

Download the server pack

On the modpack’s CurseForge/FTB/Modrinth page, download the file labeled Server Pack or Server Files — not the client installer.

Clear old files

Stop your server. Using the File Manager or SFTP (File Management), remove or archive the old server files (after backing up).

Upload and extract

Upload the server pack .zip to the server’s root directory and use the File Manager’s Unarchive option to extract it. Make sure folders like mods/ and config/ end up in the root, not nested inside an extra folder.

Set the startup jar

Point the server’s startup at the pack’s server jar or launch script — on our panel this is set under Startup parameters. If the pack ships a start.sh/run.sh installer script, contact support if you’re unsure how to wire it up.

Accept the EULA and start

Ensure eula.txt contains eula=true, then start the server and watch the console until loading completes.

Matching Client and Server

Players must run the same modpack and version as the server:

CurseForge packs — install via the CurseForge App, select the exact same pack version.
FTB packs — install via the FTB App.
Modrinth packs — install via the Modrinth App.

A version mismatch (even a minor one, e.g. pack 1.9.2 vs 1.9.3) commonly causes registry/handshake errors on join. When you update the server pack, tell your players to update too.

How Much RAM Do You Need?

Modpacks are far hungrier than vanilla. Rough guidance:

Modpack Size	Examples	Recommended RAM
Light (under ~100 mods)	Vanilla+, small Fabric packs	4 GB
Medium (~100–200 mods)	FTB Skies, Create-focused packs	6–8 GB
Large (200+ mods)	All the Mods 9/10, RAD 2	8–12 GB
Kitchen-sink + many players	ATM with 10+ players	12 GB+

These are starting points — player count, world size, and chunk generation all add up. If you see long GC pauses or OutOfMemoryError crashes, upgrade your plan; upgrades at Wasabi Hosting keep all your files.

Common Startup Errors

Server takes forever to start

Normal for big packs — first boot can take 5–15 minutes while mods initialize and the world generates. Watch the console; as long as new log lines appear, it’s still loading.

Crash mentioning a specific mod

The crash report (in /crash-reports) names the offending mod near the top. Common causes: a client-only mod in the server’s mods folder (delete it server-side), or a missing dependency mod (install it).

OutOfMemoryError / server killed

The pack needs more RAM than your plan provides. See the sizing table above and upgrade if needed.

Players get kicked with 'mod rejections' or registry errors

Client and server pack versions don’t match. Have players reinstall the exact server version of the pack.

Wrong Java version

Modern packs (1.18+) need Java 17+, and 1.20.5+ needs Java 21, while very old packs (1.12.2) need Java 8. If the console shows UnsupportedClassVersionError, the Java runtime doesn’t match — contact support or adjust the server’s Java version if your plan’s panel offers it.

Still stuck? Check the general Troubleshooting guide or send us the crash report via Discord or a ticket.

Run your modpack on Wasabi Hosting

Minecraft server hosting from €2.99/month with NVMe storage and DDR5 RAM — modpacks load fast, and you can upgrade RAM anytime without losing files.

​Mods vs. Modpacks vs. Plugins

​Mod Loaders

​Before You Start: Take a Backup

​Installing a Modpack

​Matching Client and Server

​How Much RAM Do You Need?

​Common Startup Errors

Run your modpack on Wasabi Hosting

Mods vs. Modpacks vs. Plugins

Mod Loaders

Before You Start: Take a Backup

Installing a Modpack

Matching Client and Server

How Much RAM Do You Need?

Common Startup Errors