Set up an FTB Ultimate Reloaded server

FTB Ultimate Reloaded is Feed The Beast's Minecraft 1.12.2 remake of FTB Ultimate, the pack built around big factories, farms, Railcraft rail networks and Thaumcraft magic. Feed The Beast calls it one of its lighter 1.12.2 packs. The Modpacks tab lists it under its Feed The Beast source.

Checked against FTB Ultimate Reloaded 1.11.0 on Forge 14.23.5.2855 and Minecraft 1.12.2, October 2026.

What the pack needs

• Minecraft 1.12.2, Forge 14.23.5.2855 and Java 8. These are the targets Feed The Beast lists for 1.11.0. The panel picks Java 8 for every Minecraft version below 1.17, so you do not set it.
• 4 GB of RAM as a starting point. The pack's page lists 4 GB as both the minimum and the recommended amount. Its description says a test server with a dozen or more players online sat around 2.5 GB of RAM, and that this varies with play style and forced chunk loading. Your plan sets the RAM, so read how much RAM a Minecraft server needs and check the Minecraft plans before you install.
• About 300 MB of disk. The file list for 1.11.0 adds up to roughly 200 MB, and the server read about 300 MB after the install and its first start, before the world grows.
• The same version for your players. The pack has three releases, 1.9.0, 1.10.0 and 1.11.0, and everyone needs the one your server runs. Its page is on feed-the-beast.com.

Install from the Feed The Beast source

1. Open your server and choose Modpacks under Content in the left rail.
2. Above the search box, press the Feed The Beast chip and search for Ultimate Reloaded. Searches need at least three letters. If there is no Feed The Beast chip, that source is not available on your account yet, and the steps below do not apply until it is.
3. Press Install on FTB Ultimate Reloaded. A search for just Ultimate also lists FTB Ultimate and FTB Ultimate: Anniversary Edition, which are different packs on other Minecraft versions.
4. In the window that opens, leave the version dropdown on Newest that fits your server, which starts on 1.11.0. Pick an older release there only if your players are stuck on it.
5. Leave Take a backup first ticked. An install replaces the server's files, so the backup is your way back. If the install stops with "Couldn't start a backup. Free a backup slot, or untick the backup and try again.", this usually means every backup slot is in use. Delete a backup on the Backups tab, or remove protection from a protected one, then try again.
6. Tick Start the server when it's ready only if you have already started this server once and accepted the EULA. On a new server it does not start by itself, so leave it unticked and start it yourself afterwards. Then hold Install and reinstall until it fills. The install takes about half a minute, and the console ends with Pack installed. Launch: -jar forge-1.12.2-14.23.5.2855.jar nogui.

Install an FTB modpack on your Minecraft server covers the same tab for other Feed The Beast packs.

First start

Press Start on the Console tab and accept the EULA when the panel asks. The server is up when the console prints a line containing For help, type. The first start of 1.11.0 reached that line about 75 seconds after Start. Your address is in the left rail with a copy button, and Connect to your server for the first time covers adding it in Minecraft.

The install writes a minimal server.properties with just the server address and port, and the server fills in the rest the first time it starts. After that start, open the Config Editor and set Player slots for the group you expect. Its help text calls View distance (chunks) the biggest lever on RAM and CPU, so lower it first if the server struggles.

Common problems

• A player cannot join. Check they run FTB Ultimate Reloaded 1.11.0 on Minecraft 1.12.2. Join a modded server from your launcher shows the steps.
• The install stops part way. The tab shows "The last install didn't finish" with Show install log and Retry install.
• The server lags or runs out of memory. Watch the RAM card on the Console tab and the TPS reading in the left rail. Why is my server lagging has more.
• The server crashes at boot. Find and read a crash report shows how to name the mod at fault. Pack bugs go to Feed The Beast's issue tracker.