How to Install Modpacks on Your Minecraft Server
Modpacks bundle dozens or hundreds of mods into a single download. Getting them running on a server is straightforward once you understand the process.
Forge vs. Fabric: Which Loader Do You Need?
Before installing any modpack, you need to know which mod loader it uses. The two main options are Forge and Fabric. Forge has been around since 2011 and is used by the majority of large modpacks, including All the Mods, RLCraft, and Enigmatica. Fabric is newer, lighter, and faster to update, and is used by packs like Better MC, Cobblemon, and Fabulously Optimized. The modpack page on CurseForge or Modrinth will tell you which loader is required.
The two loaders are not compatible with each other. You cannot mix Forge mods with Fabric mods, and a Forge modpack will not run on a Fabric server or vice versa. Pick the loader that matches your modpack and stick with it.
Method 1: Server Pack Download (Easiest)
Most modpacks on CurseForge and Modrinth provide a dedicated server pack download. This is a zip file that contains everything needed to run the server side of the modpack: the mod loader, all the server-side mods, and the default configuration files. It is the fastest and least error-prone way to set up a modded server.
Go to the modpack page, click on the version you want, and look for a file labeled "Server Pack" or "Server Files." Download it to your computer and unzip it. You should see files like forge-*.jar or fabric-server-launch.jar, a mods folder, and a config folder.
Open the Pterodactyl file manager for your server. Delete or move any existing files from previous setups so you start clean. Then upload the extracted server pack files. Make sure the jar file, mods folder, and config folder are all in the root directory of the server, not inside a subfolder. Set the startup jar in your server's Startup tab to point to the correct Forge or Fabric jar file, and start the server.
Method 2: Manual Mod Installation
If the modpack does not have a server pack available, or if you want to build your own custom collection of mods, you can install mods manually. Start by setting up a Forge or Fabric server, then add individual mods to the mods folder.
For a Forge server, download the installer from the official Forge website. Choose the version that matches your modpack. Run the installer with the --installServer flag on your local machine to generate the server files, then upload the entire output to your server via the Pterodactyl file manager.
For a Fabric server, the process is simpler. Download the Fabric server launcher jar from fabricmc.net. Upload it to your server root and set it as the startup jar. On first run, Fabric downloads everything it needs automatically. Then create a mods folder if one does not exist already, and upload your mod jars into it.
Client-Side vs. Server-Side Mods
Not every mod in a modpack needs to be installed on the server. Mods fall into three categories: server-side only, client-side only, and both. Server-side mods handle things like world generation, new blocks, custom recipes, and game mechanics that the server needs to process. Client-side mods handle things like shaders, minimaps, HUD improvements, and inventory sorting that only affect what the player sees.
If you install a client-only mod on the server, it usually just gets ignored, but occasionally it can cause crashes. Common client-only mods that should not go on the server include Optifine, Sodium, Iris, and most HUD mods. The mod's page on CurseForge or Modrinth will specify whether it is client, server, or both.
Keeping Mods in Sync
The server and all connecting clients must run the exact same versions of shared mods. If the server has version 1.5.2 of a mod and a player has version 1.5.3, the connection will usually be rejected with a mod mismatch error. When you update mods on the server, let your players know they need to update their client-side installation to match.
The easiest way to handle this is to use a launcher like CurseForge, Prism Launcher, or the Modrinth App on the client side. These launchers can import modpacks by pack code or URL and handle all the mod downloading automatically. When you update the server, you can update the modpack version and tell your players to update through their launcher.
RAM and Performance Considerations
Modded servers are significantly more resource-intensive than vanilla or plugin-based servers. A light modpack with around 50 mods typically needs 4 to 6 GB of RAM. Medium packs with 100 to 200 mods run best with 6 to 8 GB. Heavy packs with 300 or more mods can require 8 to 12 GB just for the server process. Check our RAM guide for detailed recommendations by scenario.
First startup of a modded server takes longer than normal because the loader needs to initialize all the mods and generate registry data. It is normal for a heavy modpack to take three to five minutes on the first boot. Subsequent startups will be faster. If the server seems stuck during startup, check the console, it is likely still loading, not frozen.
Browse our modpack hosting page for pre-configured modpack recommendations, or jump to our plans to get started.