Minecraft Server Admin

Minecraft Server Administration Skill

Scope and Routing Boundaries

Routing Boundaries

• Use when: the task is infrastructure or live operations for Minecraft servers (deployment choice, tuning, backups, proxying, security, incident response).
• Do not use when: the task is writing plugin code (minecraft-plugin-dev) or writing mods/loaders (minecraft-modding, minecraft-multiloader).
• Do not use when: the task is WorldEdit command workflows (minecraft-worldedit-ops) or EssentialsX workflow/policy design (minecraft-essentials-ops).
• Do not use when: the task is datapack/resource-pack authoring (minecraft-datapack, minecraft-resource-pack).

Support Assets

• Read references/deployment-checklists.md when the task is an incident, rollout window, proxy change, or recovery drill and you need a compact checklist before acting.

Deployment Decision Matrix

Use this table first. Pick a deployment type before changing configs.

Deployment Type Routing

• Small SMP and most public plugin servers: use Paper baseline first.
• Use Purpur only when you explicitly need Purpur gameplay controls.
• Use Folia only when plugin compatibility has been validated for region-threading.
• Use Velocity when one process is not enough or you need separate backend roles.
• Use Fabric/NeoForge when the requirement is mod-driven, not plugin-driven.

Playbook: Performance Tuning

Step 1: Establish baseline

Collect a baseline before edits:

free -h
top -b -n 1 | head -n 25

In server console:

tps
mspt
spark healthreport

Record:

• peak player count
• MSPT at idle and at peak activity
• top plugins by CPU from Spark report

Step 2: Profile the real bottleneck

Use Spark instead of guesswork:

spark profiler --timeout 180
spark tps
spark tickmonitor --interval 10

Then identify whether the issue is:

• plugin task load
• entity count / mob farm pressure
• chunk generation / disk I/O
• garbage-collection pauses

Step 3: Apply targeted fixes

Do not tune everything at once. Apply one group at a time.

1. Chunk and simulation pressure:

• lower view-distance and simulation-distance first
• pre-generate worlds for survival-heavy maps

1. Entity pressure:

• adjust despawn ranges and mob-spawn behavior in Paper world config
• cap problematic entities where appropriate

1. Plugin pressure:

• disable or replace top offenders from Spark traces
• reduce async task frequency where plugin settings allow

Step 4: Use stable startup flags

For Java 21 on Paper/Purpur:

java -Xms10G -Xmx10G \
  -XX:+UseG1GC \
  -XX:+ParallelRefProcEnabled \
  -XX:MaxGCPauseMillis=200 \
  -XX:+UnlockExperimentalVMOptions \
  -XX:+DisableExplicitGC \
  -XX:+AlwaysPreTouch \
  -XX:G1NewSizePercent=30 \
  -XX:G1MaxNewSizePercent=40 \
  -XX:G1HeapRegionSize=8M \
  -XX:G1ReservePercent=20 \
  -XX:G1HeapWastePercent=5 \
  -XX:G1MixedGCCountTarget=4 \
  -XX:InitiatingHeapOccupancyPercent=15 \
  -XX:G1MixedGCLiveThresholdPercent=90 \
  -XX:G1RSetUpdatingPauseTimePercent=5 \
  -XX:SurvivorRatio=32 \
  -XX:+PerfDisableSharedMem \
  -XX:MaxTenuringThreshold=1 \
  -Dfile.encoding=UTF-8 \
  -jar server.jar --nogui

For under 12 GB memory budgets, reduce heap and use smaller region size.

Step 5: Verify improvements

After each change set:

spark tps
spark healthreport

Keep the change only if MSPT/tick stability improves under representative load.

Playbook: Plugin Operations

Safe plugin change workflow

1. Build a plugin inventory:

• plugin name and version
• required dependencies
• minimum server version

1. Stage updates:

• apply plugin updates in staging first
• run smoke checks: joins, teleports, economy, permissions, saves

1. Production rollout window:

• announce maintenance window
• stop server cleanly
• snapshot plugin jars and config
• deploy update batch

1. Post-rollout verification:

• watch startup logs for API warnings
• run command and permission sanity checks
• track TPS/MSPT for 15-30 minutes

Rollback checklist

• Keep previous plugin directory snapshot.
• If severe regression occurs:
  • stop server
  • restore prior plugin jars/configs
  • start and confirm login/world integrity
• Document failing plugin/version pair for future blocks.

Playbook: Proxy and Forwarding (Velocity)

Velocity baseline

velocity.toml essentials:

bind = "0.0.0.0:25565"
online-mode = true
player-info-forwarding-mode = "modern"
forwarding-secret-file = "forwarding.secret"

Backend server requirements

server.properties on backend:

online-mode=false
enforce-secure-profile=false

Paper backend forwarding support (config/paper-global.yml):

proxies:
  velocity:
    enabled: true
    online-mode: true
    secret: "paste-the-shared-forwarding-secret-here"

Use the same secret value stored in Velocity's forwarding.secret file; the backend config takes the secret string itself, not a file path.

Validation runbook

1. Confirm proxy port is reachable from clients.
2. Confirm backend is firewalled from direct internet access.
3. Join through proxy and verify:

• UUID consistency
• skin/profile forwarding
• plugin permission behavior

Common proxy incidents

• "Invalid player info forwarding":
  • mismatch in forwarding mode or shared secret between Velocity and backend.
• Random auth/session failures:
  • mixed online-mode expectations or direct backend exposure.

Playbook: Backup and Recovery

Backup policy template

Example backup script

#!/usr/bin/env bash
set -euo pipefail

DATE="$(date +%Y-%m-%d_%H-%M-%S)"
BACKUP_ROOT="/backups/minecraft"
SERVER_ROOT="/srv/minecraft"
DEST="${BACKUP_ROOT}/${DATE}"

mkdir -p "$DEST"
tar -czf "${DEST}/worlds.tar.gz" -C "$SERVER_ROOT" world world_nether world_the_end
tar -czf "${DEST}/plugins-config.tar.gz" -C "$SERVER_ROOT" plugins config
cp "$SERVER_ROOT/server.properties" "$DEST/server.properties"

Recovery drill (must be tested)

1. Stop server.
2. Restore selected backup to staging directory.
3. Validate ownership/permissions.
4. Start server in maintenance mode.
5. Verify:

• world spawn loads
• player data is readable
• key plugins initialize

1. Reopen to players.

Define targets:

• RPO (acceptable data loss window)
• RTO (acceptable restore duration)

Playbook: Live Troubleshooting

Incident triage flow

1. Classify incident:

• crash on startup
• severe lag / TPS collapse
• join/auth failures
• memory/disk pressure

1. Capture evidence first:

df -h
free -h

From server/proxy console:

spark tps
spark healthreport

1. Stabilize:

• stop risky rollout changes
• disable newest suspect plugin first
• reduce player impact (maintenance mode, temporary queue, restricted worlds)

1. Recover and document:

• apply rollback or hotfix
• document root cause and permanent preventive action

Fast symptom map

Operational Config Reference

server.properties high-impact keys

max-players=100
view-distance=10
simulation-distance=8
sync-chunk-writes=true
max-tick-time=60000
enable-rcon=false

bukkit.yml and spigot.yml

Use Spigot/Bukkit docs as authoritative for version-specific defaults and side effects. Tune conservatively and re-measure after every change set.

Paper config files

• config/paper-global.yml
• config/paper-world-defaults.yml

Adjust these only after profiling identifies an actionable bottleneck.

Deployment Patterns

Docker Compose (Paper)

services:
  paper:
    image: itzg/minecraft-server:java21
    container_name: mc-paper
    environment:
      EULA: "TRUE"
      TYPE: "PAPER"
      VERSION: "1.21.11"
      MEMORY: "10G"
    ports:
      - "25565:25565"
    volumes:
      - ./data:/data
    restart: unless-stopped

Pterodactyl/Wings notes

• Keep startup command and memory allocations consistent with tested JVM flags.
• Pin panel and Wings versions to supported combinations.
• Validate backup mount and restore workflow before production.

Security Hardening Checklist

• Keep online-mode=true unless proxy forwarding requires backend online-mode=false.
• Never expose backend Paper ports directly when using Velocity.
• Restrict RCON and panel/admin surfaces by firewall/IP allowlist.
• Rotate secrets (forwarding.secret, panel credentials, backup credentials).
• Keep plugin sources trusted; verify checksum/release source before install.
• Maintain off-host encrypted backups.
• Keep Java runtime and host OS patched.

References

Paper (primary)

• https://docs.papermc.io/paper/
• https://docs.papermc.io/paper/admin
• https://docs.papermc.io/paper/profiling/

Spigot/Bukkit (primary config reference)

• https://www.spigotmc.org/wiki/spigot-configuration/
• https://www.spigotmc.org/wiki/bukkit-configuration/
• https://www.spigotmc.org/wiki/start-up-parameters/

Proxy and ecosystem docs

• https://docs.papermc.io/velocity/
• https://spark.lucko.me/docs
• https://geysermc.org/wiki/geyser/
• https://pterodactyl.io/project/introduction.html