The Ubuntu versus Debian question turns up in nearly every “first Minecraft server” thread, and the replies are usually brand loyalty in a trench coat. For a JVM game server only a few differences change your day: kernel age, package freshness, how much memory the OS holds at idle, and whether you can install the Java version Paper wants. This comparison stays on those, because they are the ones you will live with at 2 a.m. when a restart fails.

We installed both minimal on identical 4 GB VMs, measured memory and disk right after boot, then ran the same Paper 1.21 build with identical flags on each. It is written for owners choosing a VPS template, admins who inherited a machine, and staff who have to justify the choice in a wiki page. Neither distro is faster at serving chunks. The decision is about maintenance, not speed.

Release Cadence, Kernel Age, and Support Windows

Debian freezes at release and stays frozen. Debian 13 “Trixie” landed in August 2025 with kernel 6.12, and the packages inside it barely move until Debian 14 ships, apart from security patches. Ubuntu takes that same base, refreshes it every six months, and freezes an LTS every two years in April. Debian is a snapshot with a long warranty; Ubuntu LTS is a snapshot with a newer starting point.

	Debian 13	Ubuntu 24.04 LTS	Ubuntu 26.04 LTS
Kernel at release	6.12	6.8	Newer than 6.8
Release rhythm	Every ~2 years	Every 2 years, April	Every 2 years, April
Security support	~2028	2029	2031
Extended support	LTS to ~2030	ESM with Ubuntu Pro	ESM with Ubuntu Pro
Default OpenJDK	21	21	21 or 25

• Kernel age. Newer kernels handle recent NICs, NVMe controllers, and hybrid CPU scheduling better. Older ones have fewer regressions. Neither changes TPS, because Paper is limited by the JVM and single-threaded chunk work.
• Package freshness. glibc, OpenSSL, and the default JDK are newer on Ubuntu. Debian backports fixes instead of versions, which is safer and sometimes leaves a tool two years behind.
• Support window. Both outlive your world. Neither vendor is going to strand you next year, so this should not decide it.

If the hardware is brand new, the newer kernel is the safer bet. If you want the machine to stop changing under you, Debian wins. Full release notes live at debian.org/releases/stable and ubuntu.com/server/docs.

RAM, Disk, and Idle Footprint at a Clean Boot

On our VMs, a panel-less Debian 13 install used roughly 140 MB of RAM after boot and about 1.3 GB of disk. Ubuntu 24.04 Server used roughly 420 MB and 2.6 GB. The gap is real, and it is not mysterious: snapd, cloud-init, needrestart, multipath tooling, and a larger set of enabled units. A minimal Debian install is close to a kernel, systemd, and sshd, which is exactly what a headless Minecraft box needs.

Then put it in perspective. A Paper server with -Xmx6G plus off-heap allocations will sit near 7 GB resident. The 280 MB the distro costs you is noise, and it disappears the moment you install a panel or a second service. Choose on RAM only if you are squeezing a 1 GB or 2 GB VPS, where 280 MB is a plugin’s worth of headroom.

Swap and journald defaults

Ubuntu’s installer writes a swap file, usually sized to RAM and capped by available disk, so a fresh 4 GB VPS boots with 4 GB of swap. Debian’s guided partitioning makes a swap partition, but an unattended or minimal install often leaves you with none at all. That matters: without swap, a JVM that overshoots its heap gets the OOM killer instead of a slow page file. Check with swapon --show, and on Debian add a 2 GB file if the line is empty.

Both distros persist the journal to /var/log/journal, and both let it grow. On a 25 GB VPS that quietly eats gigs. Cap it in /etc/systemd/journald.conf with SystemMaxUse=500M and restart systemd-journald, on either system, and read errors with journalctl -u minecraft once logs are trimmed.

Package Tooling: Snaps, PPAs, and apt-Only

Ubuntu ships software-properties-common, so add-apt-repository works out of the box, PPAs are one command, and snapd is installed and running whether you want it or not. Debian is apt and nothing else by default: no snapd, no PPAs, third-party repositories added by hand with a signed keyring, and newer packages pulled from backports rather than a vendor channel.

Where Ubuntu annoys people running servers:

• Snap auto-refresh can restart a snapped service on its own schedule, which is the last thing you want mid-backup.
• Every snap is a loopback mount, so df output fills with noise on a small disk.
• PPAs are pinned to a release name. Upgrade to the next LTS and third-party entries break until you re-add them.

Where Debian annoys people: no PPA convenience, and if you want a newer Maven, JDK, or monitoring agent you either enable backports or manage an external repo and its key yourself. Since Debian 12, apt-key is gone and every third-party repo needs signed-by= in the source line, which trips up copy-pasted tutorials.

Java: Default Repos, Temurin, and the Same systemd Unit

Java is the one package that genuinely decides whether your server boots. Modern Paper builds target Java 21 and newer, and the newest Mojang versions have started pushing toward 25. Debian 13 and Ubuntu 24.04 both ship OpenJDK 21 in the default repos, so apt install openjdk-21-jre-headless works on both and gets you a working server today.

When the repo is behind, the fix is identical on both distros. Adoptium publishes a signed apt repository for Debian and Ubuntu, and a plain tarball for anything else, so adoptium.net gives you Temurin 21 or 25 with the same two commands regardless of which base you chose. That is the great equalizer: no distro has a monopoly on a good JDK.

The service definition does not change either. Create /etc/systemd/system/minecraft.service:

[Unit]
Description=Paper Minecraft Server
After=network-online.target

[Service]
User=minecraft
WorkingDirectory=/opt/minecraft
ExecStart=/usr/bin/java -Xms4G -Xmx4G -XX:+UseG1GC -jar paper.jar --nogui
Restart=on-failure
RestartSec=10
LimitNOFILE=65536

[Install]
WantedBy=multi-user.target

Then systemctl daemon-reload, enable --now minecraft, and check java -version reports the same build your unit points at. On Debian, install openjdk-21-jre-headless; on Ubuntu, the same. The unit above is byte-for-byte portable. Paper’s own requirements are at docs.papermc.io.

Support Ecosystem, Host Images, and Picking One

Ubuntu has more tutorials, and the numbers are not close. Ask a search engine how to install anything, and the top results assume Ubuntu. Paper’s docs use Debian-family commands but lean on Ubuntu examples, and most video guides for panels, backups, and firewalls are recorded on Ubuntu. Debian rewards command-line fluency: fewer guides, but the ones that exist are accurate, and the system is small enough that you can read what it does.

Hosting images tell their own story. Most game panels, including Pterodactyl’s yolks images, are built on Debian slim. If you rent a Minecraft panel, you are already running Debian underneath, whether or not the marketing says so. If you rent a plain VPS and pick the template yourself, Ubuntu is usually the default for a reason: more hand-holding when the network stack misbehaves.

Decision table

Your situation	Pick	Why
First home server, learning as you go	Ubuntu Server LTS	More guides, newer kernel for recent hardware
Small 2-4 GB VPS, one Paper server	Debian stable	Lowest idle footprint, fewer services to patch
Rental host or panel image	Whatever ships	The provider controls the kernel and updates
Single-purpose headless box, set and forget	Debian stable	Frozen packages, minimal moving parts

And when the answer is simply “whatever the host offers,” that is fine. Both need the same three hardening steps: key-only SSH, a default-deny firewall (ufw or nftables), and unattended-upgrades for security patches. Our SSH keys and UFW firewall guide covers the exact rules, and the 10-minute Ubuntu Server install guide walks the other path end to end.

Pros and Cons of Each

Ubuntu Server

• Pros: newest kernel and JDK, the largest tutorial ecosystem, HWE kernels, five years of free security updates, predictable April LTS dates.
• Cons: snapd runs whether you want it or not, roughly 300 MB more RAM at idle, more enabled services, release upgrades every two years if you chase them.

Debian stable

• Pros: smallest idle footprint, no snap layer, glacial package churn, the base every game panel image is built from, excellent documentation for admins who read it.
• Cons: older kernel and userland, no PPAs, third-party repos need manual keyring work, and fewer beginner-oriented guides that match your exact version.

Common Mistakes and How to Avoid Them

• Installing a desktop. Ubuntu Desktop adds a display server and a browser stack, costing 700 MB to 1.2 GB of RAM that should be heap. Use Server or Debian with no GUI.
• Running the server as root. Create a minecraft user and run the unit as that user. A plugin exploit should not get root on the host.
• Ignoring swap on Debian. No swap file plus a tight heap means the OOM killer, not a slowdown. Check swapon --show before you blame Paper.
• Applying random tuning guides. Swappiness and dirty-ratio tweaks pasted from a 2014 forum post usually hurt. Measure first, change one thing, keep notes.

Frequently Asked Questions

The Short Answer

For a first server or a VPS on current hardware, install Ubuntu Server LTS. For a lean, single-purpose box you intend to leave alone, install Debian stable. Everything above that layer, from the Paper jar to your plugin list to the JVM flags, is identical, which is the most useful fact in this whole comparison. Pick one, harden it, and spend your time on view distance and heap sizing instead of distro shopping. When a plugin inevitably fails, our guide to reading Minecraft server logs will get you to the cause faster than a reinstall ever will.