Set up the Stoneopolis modpack server

Stoneopolis is a question-based modpack for Minecraft 1.20.1 on Forge, by the CurseForge author benbenlaw. Its page describes a custom world made of stone with empty caves, more than 100 game stages that hide progression until you unlock it, and mods such as Caveopolis, Blood Magic and Immersive Engineering. You install the server from the Modpacks tab, using the pack's CurseForge server pack.

Checked against Stoneopolis 4.1 (the CurseForge file dated 31 May 2024) on Forge 47.2.20 and Minecraft 1.20.1, October 2026.

What the pack needs

• Minecraft 1.20.1 with Forge 47.2.20. The server pack's variables.txt names both. Minecraft 1.20.1 runs on Java 17, which the panel picks for you.
• Version 4.1, not 4.2. The newest file, 4.2, has no server pack on CurseForge, and its changelog reads "added new server information". The panel installs the newest file that does have a server pack, which is 4.1. Compared with 4.1, the 4.2 file updates Caveopolis and Ender Trigon and adds Desired Servers. Have players install Stoneopolis 4.1 from the pack's file list on CurseForge so their mods match the server.
• Memory. The server pack holds 118 mod jars. The author's page says a 4 GB plan suits the pack. Your plan sets the RAM, so see how much RAM a Minecraft server needs and the Minecraft plans.
• Disk space. The server pack is a download of about 248 MB and unpacks to about 291 MB. The download sits on your plan's disk while it unpacks, so you need room for both.

Install the server

1. Open your server and choose Modpacks under Content in the left rail.
2. Press the CurseForge chip above the search box, then search for Stoneopolis.
3. Pick Stoneopolis.
4. Press Install. The popup says it reinstalls your server with the pack and names Forge and Minecraft 1.20.1.
5. If the popup has a version dropdown, leave it on Newest that fits your server, which gives 4.1. Do not pick 4.2, because it has no server pack.
6. Leave Take a backup first ticked. Your current world is replaced by the pack's. Tick Start the server when it's ready if you want it to start itself, and tick I agree to the Minecraft EULA if the popup shows it.
7. Hold Install and reinstall until it fills, then wait for the install to finish.

The pack ships no Forge files of its own, so the install reads variables.txt and sets up Forge 47.2.20 itself.

First start

Press Start on the Console tab. If the EULA has not been accepted yet, the panel asks you to accept it first. The server is up when the console prints a line containing For help, type. Your address is shown in the left rail, with a copy button beside it. Connect to your server for the first time covers adding it in Minecraft, and joining a modded server from a launcher covers the client side.

Settings the pack ships

The server pack includes its own server.properties, and the install keeps it. It sets level-type=skyblockbuilder:skyblock, max-players=10, allow-flight=true and max-tick-time=120000. In Config Editor the last three are Player slots, Allow flight and Watchdog timeout (ms).

Common problems

• A player cannot join. Check they run Stoneopolis 4.1 on Minecraft 1.20.1 with Forge, then compare their mod list with the server's mods folder.
• The install stops while unpacking. Your plan's disk may be too small. Check Disk Analyser, clear space and install again.
• The server lags. 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.