// modpack server guide
Cobblemon Fabric server hosting & setup guide
A Cobblemon Fabric server needs Java 21 and about 2.5–4 GB of RAM for up to 15 players.
The official modpack of the Cobblemon mod, for Fabric!
Summary from Cobblemon Official Modpack (Fabric) on Modrinth.
Cobblemon Official Modpack (Fabric) is a Fabric modpack for Minecraft 1.21.1 (older versions go back to 1.20.1) with 73 mods, 32 of which run on the server. We'd pick our Standard plan (4 GB) for it.
Quick facts
| Loader | Fabric |
|---|---|
| Minecraft versions | 1.21.1, 1.20.1 |
| Java needed | Java 21 for Minecraft 1.21.1Older pack versions: Java 17 for 1.20.1. Java version chart. |
| Mods | 32 run on the server73 in the pack. The other 41 are client-only, and the server skips them. |
| RAM | About 2–2.5 GB for 1–3 playersBy player count. |
| Downloads | 11,054,717 on Modrinth |
| Last updated | September 13, 2026 (version 1.8.1) |
| First published | November 28, 2022 on Modrinth |
| Server support | Required: the pack has mods that must run on the server. |
| Server pack | Server Files - Cobblemon Modpack [Fabric] 1.8.1.zipOfficial server pack on CurseForge, for Cobblemon Official Modpack [Fabric] 1.8.1, the same version Modrinth has. Checked October 5, 2026. |
| Modrinth tags | adventure, lightweight, optimization |
Cobblemon Fabric on a server: what to know
The Cobblemon Official Modpack keeps the Fabric server side small. Version 1.8.2 came out on 11 October 2026, after the 1.8.1 release the facts above were read from, and its server files hold a Fabric launcher jar (loader 0.19.5), start scripts set to -Xmx4G and ten mods: Cobblemon 1.8.2 and Fabric API plus helpers such as Lithium, FerriteCore and Krypton. The modpack page says both the pack and its server package can connect with vanilla Cobblemon servers and clients, and recommends at least 2.5 GB, or 3 GB or more for best performance.
Server settings live in config/cobblemon/main.json: storageFormat picks nbt (the default), json or mongodb for party and PC data, and shinyRate (1 in 8192) and pokemonPerChunk tune spawning. Cobblemon 1.8.0 added Alpha Pokémon, TMs, the Habitat Block for controlled spawning on servers, and an option to turn off Pokémon spawning per world.
Watch out for
- Party and PC data is written to disk every 30 seconds by default (pokemonSaveIntervalSeconds), so a crash or a killed process can lose up to that much progress. Source.
- The modpack page recommends the Fabric edition over the separate NeoForge pack because it performs better. Source.
Sources: modrinth.com, curseforge.com, wiki.cobblemon.com, gitlab.com, gitlab.com (2). Checked October 12, 2026.
Cobblemon Fabric server files
Yes, on CurseForge. Modrinth has no separate server pack for Cobblemon Fabric, but the authors publish one on CurseForge: Server Files - Cobblemon Modpack [Fabric] 1.8.1.zip, for Cobblemon Official Modpack [Fabric] 1.8.1 (September 16, 2026). That's the same version Modrinth has.
How much RAM does a Cobblemon Fabric server need?
| Players online | RAM | DSN plan |
|---|---|---|
| 1–3 players | About 2–2.5 GB | Standard (4 GB) |
| 4–8 players | About 2–3 GB | Standard (4 GB) |
| 9–15 players | About 2.5–4 GB | Standard (4 GB) |
Estimated from 32 mods on the server with our RAM calculator, not measured: low end if players stay together, high end if they spread out.
Set Java's heap (-Xmx) 10–15% under the RAM you have, about -Xmx3500M on 4 GB. Fabric 1.21.1 takes it in the java command (-Xmx), usually in the start script. RAM guide.
Cobblemon Fabric server requirements
| Java | Java 21 |
|---|---|
| Loader | Fabric for Minecraft 1.21.1 |
| CPU | Fast single-core speed (one main thread). |
| RAM | About 2–4 GB for 1–15 players (table above) |
| Disk | The server files, a growing world and backups |
| Network | TCP port 25565 open to players |
Recommended plan
Our pick for Cobblemon Fabric
Standard
4 GB RAM · planned launch price $16/month
At about 32 Fabric mods this is a light pack, so 4 GB of RAM covers it for a small group.
Ordering is closed until we relaunch. We aren't taking orders or payments while we move to new hardware. Join the launch list and we'll email you when Standard servers open.
More than 15 players, or lots exploring at once? Go up to Premium (8 GB). Not sure? Email hello@dsnservers.com.
Planned launch price in USD, billed monthly once ordering opens, with a 7-day refund window.
How to make a Cobblemon Fabric server on your own PC
What's specific to Cobblemon Fabric, step by step. The full walkthrough for any pack: how to make a modded Minecraft server.
- Install Java 21.
Check with
java -version. Java version chart. - Get the server files.
Download the official server pack,
Server Files - Cobblemon Modpack [Fabric] 1.8.1.zip, from CurseForge and unzip it into an empty folder. - Start it and accept the EULA.
Run the start script in the server files, or
java -jaron the Fabric 1.21.1 server launcher, then seteula=trueineula.txtif you accept Mojang's EULA (EULA step). - Set the RAM with
-Xmx, sized from the table above. - Let friends connect: forward TCP 25565, or use a tunnel or host behind CGNAT (can't connect?).
Or run Cobblemon Fabric on DSN
Once we relaunch (join the launch list), on DSN you'd install Cobblemon Fabric from the panel's Modrinth modpack installer (version 1.8.1), pick Java 21 on the Startup tab and accept the EULA in the console. No port forwarding.
How to play Cobblemon Fabric with friends
Each player installs Cobblemon Fabric version 1.8.1 with the Modrinth App or Prism Launcher, the same version as the server, and adds the server's address under Multiplayer.
Different versions of Cobblemon Fabric on the server and a client show up as Mismatched mod channel list or mod rejections. Why friends can't join, timeouts included.
Lag and performance on Cobblemon Fabric
Can't keep up! Is the server overloaded? means ticks take longer than 50 ms; more RAM won't fix that once Cobblemon Fabric has enough (tick lag guide). For Cobblemon Fabric:
- Measure first: spark's
/spark tpsand profiler work on 1.21.1 and name the mod or machine using the tick time. - Distances:
view-distance=8and a lowersimulation-distanceinserver.properties. - Pre-generate: Chunky for 1.21.1,
/chunky radius 3000then/chunky start, before people explore.
Common Cobblemon Fabric crashes
What a Fabric 1.21.1 server running Cobblemon Fabric hits most. For any other error, paste the log into the free crash log analyzer.
- Wrong Java version. Cobblemon Fabric on Minecraft 1.21.1 needs Java 21. Started on Java 17, it stops with
UnsupportedClassVersionError: ... class file version 65.0, this version of the Java Runtime only recognizes class file versions up to 61.0. Java version fix. - Out of memory. Cobblemon Fabric (32 mods on the server) needs about 2–2.5 GB for 1–3 players;
java.lang.OutOfMemoryErrormeans it ran out. Out-of-memory fix. - Client-only mod on the server. Cobblemon Fabric includes 41 client-only mods, which a server install skips; copying a player's mods folder brings them back and stops the server. Check a mods list with the client-or-server-side checker. Client-only mod fix.
- After adding or updating a mod. Mods you add to Cobblemon Fabric by hand usually crash it with a missing dependency or a mixin conflict.
- Ticking entity or block entity. The crash report names it and gives its coordinates. Ticking entity fix.
Updates and support
Before moving Cobblemon Fabric past version 1.8.1, back up the world: see updating a modpack server without losing your world.
Bugs in Cobblemon Fabric itself go to its authors: issue tracker, wiki and Discord. Server problems on DSN: hello@dsnservers.com or Discord.
Packs like Cobblemon Fabric
More: Cobblemon server hosting, all modpack guides and how to make a modded server.
Run Cobblemon Fabric on DSN when we relaunch.
Our pick, Standard: 4 GB, planned at $16/month.
DSN Servers isn't affiliated with Cobblemon Official Modpack (Fabric) or Modrinth. The pack's icon, summary and stats come from Modrinth's public API (checked October 4, 2026).