How to Set Up an ATM10 Server: Server Files, RAM and Java 21

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Set up an ATM10 server: get the official server files, let the start script install NeoForge, run Java 21, raise the 8GB heap to fit your RAM and pregenerate.

A Minecraft campfire in a snowy forest below mountains at sunset

You want an All The Mods 10 server for your group, and three questions come first: which files to download, how much RAM to give it and which Java to run. This guide answers them and sets up ATM10 from the official server files, on your own machine or on any host that gives you SFTP access and a startup tab. If you are looking for ATM10 server hosting rather than a setup job, our All The Mods 10 server hosting page has plans sized by player count.

Quick answer: To set up an ATM10 server, download the ATM10 server files (ServerFiles-8.4.zip, under Additional Files of ATM10 8.4 on CurseForge, not the client pack), put everything in it on the server, select Java 21 and run startserver.sh (startserver.bat on Windows). The first run installs NeoForge 21.1.265 and stops at the EULA: set eula=true in eula.txt and start again. Plan for 12GB of RAM for 1 to 5 players, raise the shipped -Xmx8G in user_jvm_args.txt to fit your plan, and pregenerate the world. ATM10 8.4 came out on 29 October 2026 and its server files followed on 1 November, so the server and your players can all run 8.4.

What You Need

ItemATM10 8.4
Released29 October 2026
Minecraft1.21.1
LoaderNeoForge 21.1.265 (the start script installs it)
Java21
Server filesServerFiles-8.4.zip, about 1.26 GB
Mods in the server files469
RAM12GB for 1 to 5 players, 16GB for 5 to 15, 32GB past that

The official server files set an 8GB Java heap (-Xmx8G in user_jvm_args.txt), and Java needs memory on top of the heap, which is why this guide starts ATM10 at 12GB. Sizing questions, including CPU and storage, are answered in our ATM10 server requirements guide.

ATM10 8.4 and Its Server Files

ATM10 8.4 was uploaded to CurseForge on 29 October 2026. Its changelog moves NeoForge to 21.1.265 and lists mostly fixes (structure generation, recipe conflicts, missing silver processing recipes, quest translations) plus the Neo Vitae: BloodBorn resource pack. When we checked on 31 October 2026, the 8.4 file had no Additional Files yet; ServerFiles-8.4.zip appeared there on 1 November 2026.

Better Compatibility Checker, which ships with the pack, compares the pack version set in each side's config ("8.4" in both the 8.4 server files and the 8.4 client pack) and shows an X next to the server in the multiplayer list when they differ, so move the server and every player to 8.4 together. In the CurseForge app, a player picks the version under My Modpacks: hover over ATM10, click the small arrows button next to Play and choose it from the version list.

If you are updating an 8.3 server, back up first. NeoForge changes from 21.1.259 to 21.1.265, and the start script only installs NeoForge when there is no libraries folder, so delete libraries and copy in the new start scripts and installer along with the new mods, config, defaultconfigs and kubejs folders. Our ATM10 update guide walks through it.

Step 1: Download the ATM10 Server Files

The official ATM server guide gets them from CurseForge:

  1. Open All The Mods 10 on CurseForge and click Files
  2. Pick the version your players will use: 8.4 (29 October 2026) is the newest, with server files since 1 November 2026
  3. Scroll to Additional Files and download ServerFiles-8.4.zip, not the client pack All-the-Mods-10-8.4.zip

Do not build a server by copying mods from a client install. The 8.4 client pack lists 499 CurseForge files, while the server files carry 469 mods: the difference is client-side content the server leaves out on purpose.

Step 2: Upload Them to the Server

On your own machine, extract the zip into its own folder. On Linux, make the script executable once with chmod +x startserver.sh.

On a hosted server, the official guide's advice is to set up a fresh NeoForge server on the pack's NeoForge version first if your host offers that (21.1.265 for 8.4), then upload the files over SFTP (FileZilla works) with the credentials from your control panel:

  1. Extract the zip on your computer
  2. Upload everything in it: startserver.sh, startserver.bat, user_jvm_args.txt, the NeoForge installer and the mods, config, defaultconfigs, kubejs, datapacks and local folders. That is about 2,200 files, so check that the transfer finished without errors
  3. Leave server-ip in server.properties alone. The official guide warns that editing it can stop the server from starting

If your host has no SFTP, the guide suggests uploading the zip itself and extracting it in the host's online file manager.

Step 3: Set Java 21

ATM10 needs Java 21. On a panel you pick it in the Startup tab; on your own machine, install a Java 21 build and check it with java -version. The start script stops with "Minecraft 1.21 requires Java 21" if Java is missing or older than 21. With several Java versions installed, set the environment variable ATM10_JAVA to the full path of the Java 21 binary and the script uses that one. Our ATM10 Java version guide covers Java 25 and the install commands.

Step 4: Start It and Give It Your RAM

You do not need your own start script. The server files come with startserver.sh (run it with ./startserver.sh), which installs NeoForge on the first run and then starts it like this:

java @user_jvm_args.txt @libraries/net/neoforged/neoforge/21.1.265/unix_args.txt nogui

There is no server.jar. If your panel asks for a startup command, use this line with the NeoForge version from the top of the startserver.sh you uploaded (NEOFORGE_VERSION=21.1.265 for 8.4), because the version in the path changes with the pack: 8.3 used NeoForge 21.1.259.

The memory and garbage collector flags live in user_jvm_args.txt, which ships with -Xms4G, -Xmx8G and Aikar-style G1 flags. Raise -Xmx to fit your server and leave a couple of GB free for Java itself: on a 16GB plan, something like -Xmx13G. If you leave it at 8G, the extra RAM you pay for sits unused. Which flags to keep, and when Generational ZGC is worth a try, is covered in our ATM10 JVM arguments guide.

Step 5: Accept the EULA

The first start installs NeoForge (do not interrupt it) and then stops because the EULA is not accepted yet. Set eula=true in eula.txt and start again. The official guide says the server is ready once the console shows "Dedicated server took xx seconds to load".

The script restarts the server 10 seconds after any exit unless the environment variable ATM10_RESTART is set to false.

Step 6: Check server.properties

On the first start the script writes a server.properties with the pack defaults, but only if the file does not exist yet:

allow-flight=true
motd=All the Mods 10
max-tick-time=180000
simulation-distance=5
view-distance=8

Start with those. allow-flight=true keeps players with jetpacks from being kicked for flying, and max-tick-time=180000 gives a stuck tick 3 minutes before the watchdog stops the server, where vanilla allows one minute. With 469 mods, every extra chunk of view distance costs noticeably more than on vanilla, so raise it in small steps and watch the tick time.

Step 7: Pregenerate the World

The pack ships no pregeneration mod, but NeoForge has a command built in, so you do not need Chunky:

/neoforge generate start 0 64 0 313

The last number is a radius in chunks, not blocks: 313 chunks is about 5,000 blocks from the center, and NeoForge accepts up to 2,500. The command needs permission level 4, so run it from the console or as a level 4 op. Check progress with /neoforge generate status and stop it with /neoforge generate stop. Let it finish before players join.

It only generates the dimension it runs in. From the console, use execute in for the others, for example:

/execute in minecraft:the_nether run neoforge generate start 0 64 0 100

Running It Day to Day

Do not strip mods. Every player needs the same pack as the server, so removing mods from the server means it no longer matches what players run. The official server files already leave out the client-side mods.

Item Clear is on. ATM10 ships Crash Utilities with Item Clear turned on: every 5 minutes it clears dropped items when there are more than 1000 on the ground, with chat warnings 20 and 5 seconds before. Tell your farm builders, or change it in config/crashutilities-server.toml.

Backups. The server files ship no backup mod. Schedule backups in your panel, or copy the world folder yourself before every change.

Scheduled restarts. The start script only restarts the server after it stops. If you want a daily restart, set it up as a scheduled task in your panel.

Updates. ATM10 updates can remove mods and change recipes, and the 8.3 and 8.4 changelogs both end with "ALWAYS REMEMBER TO BACKUP BEFORE UPDATING". Back up first, test the new version on a copy, and only then update the live server.

Common ATM10 Server Problems

The server will not start or crashes straight away. Usually one of: not enough RAM, Java older than 21, the EULA not accepted yet, a corrupted mod file from an interrupted upload, or a libraries folder left over from an older NeoForge version. Read the console from the top for the first error.

TPS keeps dropping below 19. Use /neoforge tps to see the tick time per dimension, then profile with spark, which ships with ATM10, to find the mod or the build causing it. Our ATM10 lag fix guide goes through the usual causes.

It crashes during chunk generation. Check that -Xmx fits your plan, and pregenerate so the server is not generating terrain while players play.

Players cannot connect. Make sure the server finished starting (watch the console), that port 25565 or your assigned port is open, and that every client runs exactly the same ATM10 version. Better Compatibility Checker shows a tick or an X next to the server in the server list, and an X means the versions differ.

Paper or Purpur? No. ATM10 runs on NeoForge. Paper and Purpur are Bukkit-based and cannot load NeoForge mods.

Which Plan Fits

PlayersRAMSpace-Node planStandardPremium
1 to 512GBMC Special 1EUR 10.80/monthEUR 21.99/month
5 to 1516GBMC Special 3EUR 14.40/monthEUR 27.99/month
15+32GBMC Special 4EUR 29.99/monthEUR 56.99/month

Prices as of 31 October 2026 for the Netherlands, Germany and Poland; the plan selector on our ATM10 hosting page shows the other regions. How many players a plan really carries depends on loaded chunks and running automation, so start with the RAM the pack needs and move up a size if TPS drops under load.

Standard plans run on the AMD EPYC 7443 with DDR4 in the Netherlands, Germany and Poland, and Premium on the Ryzen 9 9950X with DDR5. NVMe storage and DDoS protection come with every plan, and the CPU is shared on every plan, Premium included. You pick the Java version in the Startup tab and edit user_jvm_args.txt in the file manager or over SFTP.

FAQ

How much RAM should I allocate to an ATM10 server? Plan for 12GB of server RAM for 1 to 5 players, 16GB for 5 to 15 and 32GB past that, then set -Xmx in user_jvm_args.txt 2 to 4GB below the plan size, for example -Xmx13G on 16GB. The official ATM guide asks for at least 6GB allocated for most ATM packs, but ATM10's own server files already set an 8GB heap. The requirements guide has the details.

Where do I download the ATM10 server files? On CurseForge: open All The Mods 10, click Files, pick the version and download the server files under Additional Files, ServerFiles-8.4.zip for 8.4. The main download is the client pack, which cannot run as a server. Our ATM10 server files guide explains the difference in more detail.

How big is ATM10, and how many mods does it have? The 8.4 server files are a 1,256,676,660-byte zip, about 1.26 GB, that unpacks to about 1.4 GB with 469 mods. NeoForge's libraries folder and the world come on top, and the world grows as players explore. For players, the client pack is a file of about 200 MB that lists 499 CurseForge files, which the CurseForge app downloads when you install it.

Can my server run ATM10 8.4 yet? Yes. ServerFiles-8.4.zip appeared under Additional Files on the 8.4 file page on 1 November 2026, after none were listed on 31 October. When you update from 8.3, delete the libraries folder, because NeoForge moves from 21.1.259 to 21.1.265.

Sources

All opened on 31 October 2026, the 8.4 server files on 1 November 2026: