Project Zomboid Server Survival: Admin Tips for B41 & B42

Project Zomboid Server Survival: Admin Tips for B41 & B42

Tips for Project Zomboid Server Administrators

For Version B41 and B42

Last Updated: May 2025

Introduction – Surviving the Setup

So you've decided to run a Project Zomboid server for you and your friends (or a whole community of survivors). Good choice! Being a server admin in PZ is like being the leader of a ragtag apocalypse camp – it's rewarding, but you'll face some challenges that require creativity and grit. This article is a toolbox of tips for Project Zomboid server administrators on Build 41 and the new Build 42.

We'll start with a Quick-Start setup guide for the impatient, then dive into performance tweaks, mod management, security against griefers, and advanced tricks to keep your server running smoothly. By the end, you'll know how to handle everything from installing mods to stopping a horde of trolls (sometimes literally!).

Whether you're hosting a cozy co-op server for a few friends or administering a bustling public server with dozens of players, these tips will help you avoid common pitfalls. We'll cover in-game admin tools, configuration files, hardware advice, and what changes Build 42 brings to the table. Let's turn you from a survivor into the ultimate server Overseer (with admin powers comes great responsibility, after all).

Grab your axe and your notepad, and let's get started!

Quick-Start Guide to Hosting (B41/B42)

If you're new to hosting, here's a Quick-Start checklist to get your Project Zomboid server up and running fast. This assumes you want a basic server for Build 41 or 42 with default settings:

  1. Decide How to Host: For 2-4 friends, using the in-game Host option can be simplest. Launch PZ, click Host, create a server name and admin password, and start the server. The game will auto-handle port forwarding via Steam in many cases (UPnP) and create config files. (Downside: the server only runs when you're in-game and performance may suffer if your PC isn't beefy.) For a more permanent or larger server, use the dedicated server application (either on your own hardware or through a hosting provider).
  2. Install Server Files: If going dedicated, install Project Zomboid Dedicated Server via SteamCMD or Steam. On Steam, it's listed under Tools. On SteamCMD, run:
    steamcmd +login anonymous +force_install_dir /pzserver +app_update 380870 validate +quit

    This installs the latest server (Build 41 by default). For Build 42 unstable, use the -beta unstable branch.

  3. Configure Ports: Ensure ports 16261 UDP (game port) and 8766/8767 UDP (Steam ports) are forwarded in your router if hosting at home. Also allow ProjectZomboidServer.exe through your firewall. If friends can't join, 90% of the time it's a port issue or firewall blocking.
  4. Initial Server Settings: Locate the server config files. On Windows, after first launch they are in C:\Users\<YourName>\Zomboid\Server\. Open servertest.ini in a text editor. At minimum, set:
    • Public=true/false (false if it's just for friends)
    • Password= if you want to password-protect
    • DefaultPort=16261 (change only if running multiple servers)
    • DefaultGameMode= and Map= usually "Sandbox" and "Muldraugh, KY"
    • AdminPassword= - Set this to something secure
  5. Launch and Test: Start the server. If using the dedicated server, run the ProjectZomboidServer.bat (Windows) or the start script (Linux). Now launch Project Zomboid (game client), go to Join, and input 127.0.0.1 if hosting on the same PC or your server's IP. Use username "admin" and the admin password you set.
  6. Invite Friends: Give friends your external IP (Google "my IP" to get it) or use the Invite via Steam feature. Make sure they have the exact same game version (Build 41 or opted into the 42 beta).
  7. Set Yourself as Admin: By default, the first account "admin" with the password is the superuser. If you want to make your player account admin, from the server console type:
    setaccesslevel "YourUsername" admin

    In chat (in-game) you would use /setaccesslevel YourName admin. After that, relog or use /grantadmin YourName.

  8. Save Settings and Go: If everything works with default settings, you're good to play. Survivors can join, and zombies await. But you'll likely want to adjust loot, zombies, etc., which we'll cover next.

This quick-start got you running; the sections below will turn this barebones setup into a finely tuned apocalypse experience.

Choosing Your Hosting Approach

One of the first decisions is how to host: use the built-in Host feature or set up a standalone dedicated server. Both have pros and cons:

In-Game Host (Co-op mode)

Advantages:

  • Easiest to set up - just click Host in the main menu
  • Friends join through Steam's friend list (no IPs needed)
  • Perfect for quick sessions or casual play
  • Auto-configures most settings

Disadvantages:

  • Your PC's resources are shared between playing and hosting
  • Server shuts down when you exit the game
  • Less stable for larger groups (5+ players)
  • Limited advanced configuration options

Ideal for: Small groups of 2-4 friends who play together at the same time.

Dedicated Server

Advantages:

  • Runs continuously, even when you're offline
  • Players in different time zones can play on their schedule
  • More stable for larger groups and heavily modded setups
  • Full control over server configuration

Disadvantages:

  • More complex setup and maintenance
  • Requires dedicated hardware or hosting service
  • Need to manage configuration files and network issues
  • Higher resource requirements (4GB+ RAM recommended)

Ideal for: Larger communities, persistent worlds, or players with varying schedules.

Tip: Hosting Providers

Not keen on running a server from your home network? Consider using a game server provider. Companies like G-Portal, Nitrado, GTXGaming, etc., offer PZ servers for a monthly fee. They handle the hardware and give you a web interface to change settings.

These services can simplify mod management with one-click installs and usually have good DDoS protection and uptime. The trade-off is cost and sometimes slightly less flexibility than hosting yourself.

Tweaking Server Settings

Once the server is up, you'll probably want to adjust gameplay settings: zombie count, loot rarity, PvP on/off, etc. Project Zomboid has two types of settings: core server settings (in servertest.ini) and sandbox settings (in servertest_SandboxVars.lua).

Key Server Options (servertest.ini)

Open servertest.ini – here are some important options and recommendations:

  • Public: If Public=true, your server will be visible in the public server list. For a private friend server, set this to false.
  • Password: If set, anyone joining must enter this password. Good for a semi-private community.
  • PvP: true/false. On friend-only servers you might set PvP false to avoid accidents.
  • PauseEmpty: PauseEmpty=true will stop in-game time when no players are online. For friend servers with infrequent play, enable PauseEmpty to avoid surprises.
  • WorkshopItems & Mods: These lines manage mods. WorkshopItems lists Steam Workshop IDs and Mods lists the actual mod folder names.
  • AntiCheat: There are AntiCheat toggles (AntiCheatProtection1-15). Some legitimate mods trigger false positives in anti-cheat. For example, Brita's Weapon Pack often requires disabling AntiCheat type 12.
  • UPnP: If true, the server will attempt to automatically open the necessary port on your router using Universal Plug and Play.

Sandbox Settings (servertest_SandboxVars.lua)

SandboxVars are the gameplay tweaks: zombie count, loot rarity, etc. If you open servertest_SandboxVars.lua, you'll see a table of values:

SandboxVars = {
    Zombies = 3,
    PopulationMultiplier = 1.0,
    LootRarity = 3,
    StarterKit = false,
    ...
}

Key Sandbox settings and recommended considerations:

  • Zombie Population: PopulationMultiplier=1.0 is default. If your server is lagging, consider lowering it (0.5 = half zombies).
  • Loot Rarity: Defaults are "Normal" for everything in Survival mode. This doesn't affect performance much, it's purely gameplay.
  • Infection Mortality: If you're on a friends server and want a more forgiving game, you can disable the zombie infection (set Transmission = None).
  • Fire Spread: By default fires do spread and can burn down huge parts of the map. Many large servers turn this off to prevent griefing.
  • Safehouse options: SafehouseDaySurvivedToClaim sets days a player must survive before claiming a house. Defaults to 0 or 1.
  • Sleep: On multiplayer, players can't sleep unless you enable sleep in server options and even then it requires all players to sleep at once (impractical for public).

After changing sandbox vars, restart the server. If something seems not to apply, double-check the file format or use the GUI method to avoid mistakes.

Pro Tip: Using the GUI

If you're not comfortable editing files directly, you can use the in-game UI. On the main menu, click Host > Manage Settings, adjust everything via the GUI, and save it. The game will write the changes to the config files for you.

Managing Mods on Your Server

Mods are a huge draw for PZ – everything from new guns, maps, to admin tools and gameplay overhauls. But mods on servers can be tricky if not handled correctly. Let's break it down step-by-step, since misconfigured mods are a top cause of server problems.

Installing a New Mod

Suppose you want to add the popular Brita's Weapons mod to your server. Here's what you do:

  1. Subscribe and Check Mod ID: Subscribe to the mod in Steam Workshop. In the Workshop page URL you'll see something like ?id=2256623446 – that number is the Workshop ID. The page will also list the "Mod ID".
  2. Update Server .ini: Open servertest.ini. Find WorkshopItems= line. Add the workshop ID. For multiple mods, they go separated by a semicolon. Then find Mods= line. Add the mod's name exactly as specified. Example:
    WorkshopItems=2256623446;2256623668
    Mods=Brita;BritaGunFighter
  3. Ensure Clients Have It: When players join a modded server, if they are missing mods, the game will show a popup with a list of required mods and offer to enable/download them. It's good practice to announce mods beforehand so they can preload them.
  4. Restart the Server: Whenever you change mods, always restart the server fresh. The server on startup will log each Workshop ID and attempt to download/update them. Double-check the console log for any errors.
  5. Matching Versions: If a mod updates on Workshop, clients will auto-update but the server only checks for mod updates when it starts. This can lead to "Workshop item version different than server" kicks. The fix is to restart the server so it grabs the latest version.
  6. Anti-Cheat Adjustments: Some mods might require turning off specific anti-cheat protections. If players get inexplicable kicks after using a mod item, check the anti-cheat settings.
  7. Mod Load Order: PZ loads mods in the order they're listed in the Mods= line. If two mods modify the same thing, the last one in the list wins.
  8. Maps Mods: Want to add custom maps? These require a bit more editing. In addition to WorkshopItems/Mods entries, you must edit Map= line to include the map folder names.

Recommended Admin/Utility Mods

Cheat Menu / Rebirth

Allows admin to use an in-game menu for spawning items, toggling god mode, etc. Handy for restoring gear lost to glitches.

Caution: Be careful with permissions as it gives powerful abilities.

Server Admin Tools

Provides UI menus for kicking, banning, etc. With the official admin panel improvements, such mods are less needed now but still useful.

Feature: One-click whitelist management and player monitoring.

Update PLZ

Automatically checks for outdated Workshop mods on the server. It saves and shuts down the server when a mod update is detected.

Note: Requires using an external auto-restart script.

Map Mods

Popular ones: Raven Creek (big city), Bedford Falls (classic), Fort Redstone, Eerie Country, etc.

Tip: Account for performance impact when adding large map mods.

Important Note for B42: Build 42 has significant changes and many B41 mods will not work with it. The devs explicitly warned: "Build 41 saves and mods are NOT compatible with Build 42."

Keeping Your Server Running Smoothly

There's no quicker way to kill a fun session than server lag or crashes. Project Zomboid can be surprisingly demanding on servers, so let's talk performance optimization and maintenance.

Hardware Considerations

Recommended Server Specs

CPU

PZ server is single-thread heavy. Higher clock speed beats more cores. A CPU with good single-core performance is ideal.

RAM

At least 4GB dedicated, plus ~100-200MB per player and per big mod. For a 16-player server with lots of mods, think 6-8GB.

Storage

Server files are relatively small, but save files grow with player activity, map exploration, and accumulated items.

Network

A wired connection is recommended. Game doesn't use insane bandwidth, but ~1Mbps per 10 players in heavy action.

Performance Tips

  • Periodic Cleanup: Over time, the world can accumulate a lot of dropped loot. There are sandbox settings to make corpses decay and even disappear after a time – consider enabling corpse removal.
  • Backups: Make regular backups of your Zomboid/Server/<servername> folder. Especially do this before adding new mods or after major patches.
  • Monitoring Performance In-Game: Press F11 in-game (if admin) to see the performance panel. It shows server FPS, memory usage, etc. This can give you heads up if things are tanking.
  • Memory Management: If the server throws an "OutOfMemory" error, the Java heap might need increasing. Look for -Xmx parameter in the start script and increase it (e.g., -Xmx4g for 4GB heap).

Auto-Restart and Watchdog

Sometimes servers can hang or crash (especially modded ones). It's good to have a mechanism to auto-restart on crash. If you run via a .bat, you can loop it to restart.

Regular restarts (like a daily restart during off hours) can preempt issues and also apply mod updates. Many community servers restart every 24 hours to keep things fresh.

Admin Powers and Keeping Order

Running a server isn't just ticking checkboxes and updating mods – you're also the sheriff of this survivor town. Let's talk about admin powers and how to use them effectively (and fairly).

Admin Panel and Commands

Build 41's multiplayer introduced a robust admin panel UI. Once you're admin, you'll notice a new icon on the left of your screen – clicking that opens the panel. From there you can navigate various tabs:

Players

Shows who is online, their Steam ID, ping, etc. You can teleport to them, heal them, or ban/kick.

Safehouses

Manage claimed safehouses. If a player quit and their safehouse is blocking others, you can remove it here.

Items / Spawn Items

Search and spawn any item to your inventory. Useful to replace glitched items or give gifts to players.

Visibility and Ghost Mode

Toggle invisibility (/invisible) and god mode (/god) on yourself.

Banning and Whitelisting

To ban a player permanently, use /ban username (or through admin panel). This adds them to the banlist.txt in the server folder.

Alternatively, some admins prefer using a whitelist model – where only players you manually add can join. In servertest.ini, set Open=false, then add users via /adduser Username Password.

The server creates useful logs in the Logs/ directory. chat.txt records all chat, pvp.txt logs PvP hits/kills, and admin.txt tracks admin commands used.

Fun with Admin Commands

/createhorde count X Y

Spawn a horde of zombies around coordinates or yourself. Great for events!

/additem

Do things like a server-wide "air drop" by spawning supplies at a location.

/heli

Trigger helicopter event. Suddenly everyone hears the helicopter – chaos can ensue.

/stoprain, /startrain

Control the weather. Make a snowstorm for Christmas, or clear fog if players complain.

Always balance fun with fairness. Don't abuse powers to give your faction an undue advantage – players will notice. Many admins use a separate account for "playing" as a normal player and only use their admin account when needed.

Build 42: New Challenges and Opportunities

Build 42 (B42) is an exciting update that brings a lot of new content and some under-the-hood changes that server admins should be aware of.

No Upgrade In-Place – Start Fresh: You cannot simply load a Build 41 save on a Build 42 server. The differences in data are too big. Plan a server wipe or new world when moving to B42.

Key Build 42 Changes for Admins

Animal Husbandry

Players can find and pen animals (chickens, pigs, cows, etc.), feed and breed them. This introduces new complexity:

  • Animals need to be synced and updated on the server, consuming resources
  • Watch for performance impact if many players start hoarding animals
  • Check SandboxVars for new animal-related settings

New Professions & Crafting

B42 expands crafting (blacksmithing, pottery, etc.). For admins, consider:

  • Players might ask for skill books if something is super rare
  • Some crafting recipes are gated behind magazines that spawn rarely
  • With brewing and food crafting expanded, farming and hunting become more central

Aiming and Combat Changes

Build 42 introduced major changes to firearms aiming and perhaps rebalanced melee too. Players used to Build 41 might suddenly find their marksmanship is off.

  • Consider hosting a friendly shooting range event to let players adjust
  • You might get feedback that "guns suck now" or "too hard"
  • You can adjust HitChance settings if truly needed

Map Expansions & Wilderness

B42 expands the vanilla map with new towns and locations. It also adds randomized wilderness outside map bounds.

  • More map = more to explore, but doesn't hurt performance until players roam there
  • The first weeks, everyone will rush to new towns
  • If you enable infinite wilderness, consider server storage and performance

B42 Server Security Improvements

In Build 42, the devs have moved more calculations to the server (to combat cheating). This means B42 servers might actually have higher CPU load than B41 for the same scenario, because previously some physics or inventory logic was client-side but now server has to handle it.

The flip side is better security (no more easy item spawn cheats because server verifies everything). Keep an eye on performance initially, you might need to adjust population down a notch if you notice server load increased.

Staying Updated with B42

B42 unstable will likely receive frequent patches. If you're running it, you must update the server whenever the game updates (or players won't be able to join due to version mismatch).

Subscribe to Project Zomboid dev news, join their Discord or check the official forum News section regularly, so you know when updates hit. And obviously, backup before each update because unstable updates can introduce bugs that corrupt saves.

Keeping It Fun and Fair

Being a server admin is a bit of work, but it's also very rewarding to see a thriving community enjoying the world you host. You'll learn a lot as you go – don't be afraid to make mistakes, just communicate and learn from them. Remember that at the end of the day, everyone's here to have fun surviving the zombie apocalypse.

Adminning a PZ server is like running a neighborhood watch in zombie town. You coordinate the block party (server events), make sure no one's wrecking the place (moderation), and occasionally chase a stray dog or zombie off someone's lawn (technical issues or griefers). It's a responsibility, but also a lot of fun.

Action Steps Recap (TL;DR)

  • Set Up Right: Use the in-game Host for small groups or a dedicated server for long-term communities. Forward ports 16261 & 8766/8767 UDP.
  • Tune Performance: Adjust zombie count and settings to what your hardware can handle. Stable 30 FPS gameplay beats choppy 60 FPS aspirations.
  • Manage Mods Carefully: Always match Workshop IDs and Mod IDs in the config. Restart after adding mods. Watch out for mod updates.
  • Use Admin Tools: Familiarize yourself with admin commands and the panel. A quick /help in chat will list commands.
  • Secure the Server: Enable safehouse claiming and adjust its settings to protect players' bases on PvE servers.
  • Backup, Backup, Backup: Regularly save copies of your world data. It's your insurance against both grief and glitches.
  • Plan for B42: If not yet on B42, start preparing your community for the transition. Test B42 on a separate instance.
  • Have Fun: Run events, be a bit playful as the all-seeing admin. Create memorable experiences for your players.

Further Resources

Project Zomboid Wiki

Contains up-to-date info on every server setting and admin command. An excellent reference for exact syntax and config options.

The Indie Stone Forums

If you encounter a weird issue, chances are someone on the forums has seen it. Search the Multiplayer section or post your problem.

Project Zomboid Discord

The official Discord has a channel for server hosting where you can ask quick questions and share knowledge with other admins.

By following this guide and utilizing these resources, you're well on your way to running a top-notch Project Zomboid server. It's a learning process, but also an integral part of what makes multiplayer Zomboid so engaging – the unique servers and stories that emerge.

Good luck, have fun, and don't forget to occasionally enjoy the game as a player on your own server! After all, what's the point of ruling a zombie apocalypse if you can't partake in a little zombie carnage yourself?

Happy hosting, and remember: When life gives you zombies, make zombie stew – or better yet, let your players do it and just ensure the pot stays on the fire! 🧟‍♂️🔥