A personal Minecraft server on a VDS gives full control over the world and mods, unlike a ready-made game hosting plan: your own IP, your own plugins, your own access rules. The price of that freedom is that configuration and resource planning have to be done by hand. Here is how many cores and how much memory to budget, how to install the server, and what to do with the network so stray connections do not bring it down.
How many resources a Minecraft server needs
A Java Minecraft server depends almost entirely on the amount of RAM allocated to the Java process and on single-core clock speed — the game spreads load across cores poorly, so chasing a higher core count matters less than chasing clock speed. Picking a CPU by architecture and clock speed is covered in the article on choosing a server CPU.
The disk matters less, but an SSD noticeably shortens the time to generate new map chunks compared to an HDD, especially when players actively explore the world and the server keeps loading new chunks.
Installing the server on a VDS
On Linux, a Minecraft server runs as an ordinary Java process: it is enough to install the required Java version, download the server file, and run it with a memory limit via the -Xms and -Xmx flags. Running it inside screen or a systemd service lets the server keep working after disconnecting from the SSH session.
# Starting a Minecraft server with a 4 GB memory limit
java -Xms2G -Xmx4G -jar server.jar noguiHow many players the server can handle
An approximate relationship between the number of simultaneous players and the amount of memory and installed mods or plugins looks like this — exact figures depend on the specific mods and chunk-loading settings:
- 2–4 GB of memory — vanilla server with no mods, up to 5 players.
- 4–6 GB of memory — server with a few plugins, up to 15 players.
- 6–8 GB of memory — a medium-weight modpack, up to 15 players with headroom.
- 8–12 GB of memory — several worlds or a large modpack, up to 30 players.
- Above 12 GB of memory — modpacks with heavy world generation or a large number of plugins at once.
Network, ports, and protection from stray connections
A Minecraft server listens on port 25565 by default, and that port must be open in the VDS firewall, otherwise players simply will not connect. It is worth opening it only for the needed protocol, while everything else incoming on the server is better closed by default.
Step-by-step firewall rule configuration from scratch, including how to limit the number of connections from one address against the simplest DDoS attempts, is covered in the article on configuring iptables.
Load monitoring and what to do about lag
Server-side lag almost always comes down to one of three causes: not enough memory for the current number of loaded chunks, the CPU not keeping up with ticks because its clock speed is below what is needed, or the disk not keeping up with world autosaves. Telling these causes apart is helped by real-time resource monitoring, not guesses based on how players feel.
| Symptom | Likely cause | What to check |
|---|---|---|
| Delay when players move | not enough CPU clock speed per tick | single-core load |
| Server freezes during autosave | slow disk | world file write time |
| Memory stays near 100% | not enough RAM for chunks | -Xmx limit and player count |
| Lag affects only some players | network delay, not the server | ping to the server |
How to set up collection of these metrics and alerts before the server hits a limit is described in the article on VDS resource monitoring.
Frequently asked questions
How much RAM to give the server versus the whole system?
The -Xmx flag should be given noticeably less than the server's total RAM — the operating system and background processes need their own reserve. If the VDS has 4 GB of memory, it makes sense to leave about 3 GB for -Xmx, not all 4.
Can mods and plugins be installed without restarting the server?
For most plugins on platforms like Paper, a restart is not required — some systems reread the configuration on the fly. For mods on Forge or Fabric, a restart is almost always needed, because a mod changes code that is loaded only when the process starts.
Is a separate VDS needed for each server world?
No, several worlds usually run as separate Java processes on one VDS, as long as memory and CPU are enough for all of them at once. A separate VDS makes sense when the combined load of the worlds exceeds what one plan provides, or when the worlds must be physically isolated from each other.