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Cobblemon server hosting: RAM, plan and setup

3 min readUpdated Nov 3, 2026Copy link

Cobblemon is a Pokémon-style mod for Minecraft Java. The official Cobblemon modpack runs on Fabric for Minecraft 1.21.1 and is light enough for a small plan.

What Cobblemon is #

Cobblemon is made by Cobbled Studios. You can run it two ways: the Cobblemon Official Modpack [Fabric], which bundles the mod with a set of performance and quality-of-life mods, or the Cobblemon mod on its own (it has Fabric and NeoForge builds). Most servers use the official pack.

The pack page says the modpack and its server package can connect with plain Cobblemon servers and clients, so players can join with the official pack.

How much RAM Cobblemon needs #

The official modpack page says it is recommended to run with a minimum of 2.5 GB of memory, and to use 3 GB or more for smoother performance.

That covers the pack itself. A server also holds every area your players are in, so it needs more as people spread out. Our practical range (an estimate from the 3 GB figure, not a number from the pack):

Adding big extra mods or add-on packs raises these numbers. Watch the memory graph on the server page and upgrade if it stays near the top.

Which ESN plan fits #

Fabric servers need a plan with at least 1 GB on ESN, but Cobblemon wants 2.5 GB or more, so don't go below 4 GB for a group. Prices are the regular monthly list prices; see plans and billing.

CPU

On ESN, 100% CPU is one full core. Minecraft runs most game logic on one main thread, so a big modpack needs a strong core more than many cores. The extra cores still help with chunk loading, world generation and Java garbage collection, which modpacks do a lot of. The Minecraft-ready Pro plans give more CPU per GB (ESN Pro 8GB has 400%, ESN Extreme 8 GB has 250%), so pick Pro when players explore a lot or the pack has heavy automation.

Set up Cobblemon on ESN #

The official pack is on Modrinth, so the panel can install it for you.

1. Buy a plan and choose Fabric as the Minecraft type.
2. Open Files and choose Install a modpack. Search for Cobblemon Official Modpack and choose Install pack. It downloads the pack's server mods and config files from Modrinth and sets the Minecraft and loader versions on the Startup page. Files with the same name are kept, so take a backup first if the server already has a world.
3. When it says installed, go to Settings and choose Reinstall Server (Fabric servers show a Reinstall now button) so the matching loader is downloaded.
4. In Startup, set Docker Image to Java 21.
5. Start the server, accept the EULA prompt, and wait for Done.

Fabric servers on ESN already start with Aikar's garbage-collection flags, and the panel sets memory from your plan. For custom flags, ask in the ESN Systems Discord.

Only want the mod?

On a Fabric server, put the Cobblemon mod and Fabric API in the mods folder (use Browse mods on the Files page, or upload the .jar files). See add plugins and mods. Players then need the same Cobblemon version.

Common problems #

• "Can't keep up! Is the server overloaded?" Normal once during the first start. If it repeats while people play, profile it with spark and fix the top cause. See fix "Can't keep up".
• Players can't join, "mismatched mod list" or missing mods. Every player needs the exact same pack version as the server. Update the server and all players together.
• The server crashes at start with a client-only mod. Shaders, minimaps and menu mods sometimes only run on the client. Use the official server files, which leave them out, and don't copy your client mods folder.
• "Unsupported class file major version" or UnsupportedClassVersionError. Wrong Java version. Change Docker Image in Startup and restart.
• OutOfMemoryError or the server stops under load. The pack needs more RAM than your plan has. Lower view-distance or move to a bigger plan. See Minecraft RAM.
• Players on a different Cobblemon version. Cobblemon updates often. Update the server and tell players to update the pack at the same time.

FAQ #

How much RAM does a Cobblemon server need?

The official modpack recommends at least 2.5 GB and 3 GB or more for better performance. For a server we suggest 4 GB for up to 5 players and 6 to 8 GB for bigger groups.

Is Cobblemon Fabric or Forge?

The official modpack is Fabric on Minecraft 1.21.1. The Cobblemon mod also has a NeoForge build, and there is a NeoForge version of the pack.

Can players join with the official Cobblemon modpack?

Yes. The pack page says the modpack and server package can connect with plain Cobblemon servers and clients, as long as the Cobblemon versions match.

Does ESN install Cobblemon for me?

The panel's Install a modpack button installs the official pack from Modrinth. You then reinstall once, set Java 21 and start the server.

Sources: Cobblemon Official Modpack [Fabric] on Modrinth (2.5 GB minimum, 3 GB or more recommended; version 1.8.4, Minecraft 1.21.1, Fabric) (checked Nov 3, 2026) · Cobblemon mod on Modrinth (Fabric and NeoForge builds for 1.21.1) (checked Nov 3, 2026)

Still stuck? Use the live chat on the panel or ask in the ESN Systems Discord. Last updated November 3, 2026.