project zomboid server settings

Project Zomboid's server system revolves around a few key files and settings. If you're new to hosting, Build 41 introduced the revamped multiplayer framework and Build 42 builds upon it with new features (like an official mod manager and expanded late-game). Don't worry – the core ideas remain the same, and we'll highlight version differences as we go.

1.1 Understanding the Core Server Files

When you first install a Project Zomboid dedicated server (or host via the game's Host menu), the game generates four main files that control the game world:

• servertest.ini – The primary server config (server name, ports, PvP on/off, passwords, etc.). We'll dissect many of its settings in this guide.
• servertest_SandboxVars.lua – The sandbox settings for the world (zombie behavior, loot spawns, environment settings).
• servertest_spawnpoints.lua – Defines spawn locations for new players.
• servertest_spawnregions.lua – Groups spawnpoints into named regions that players see on join.

1.2 Using the In-Game Settings GUI

If you aren't comfortable editing text configs directly, Project Zomboid provides a handy GUI method:

1. Launch the game, go to Host > Manage Settings.
2. Click "Create New Settings" or edit an existing preset.
3. After tweaking settings, save with a unique name (e.g. "MyCoopServer1").
4. Upload or replace the server's files with these. Many server hosts allow uploading via FTP or control panel.

Using the GUI ensures you don't miss an option or make a syntax error – plus it gives explanations for each setting on the screen.

1.3 Differences in Build 42 Setup

Build 42 doesn't drastically change how you configure the server, but it brings some quality-of-life improvements:

• An official mod manager UI in-game for easier enabling/disabling of mods
• New features like animals and crafting stations introduce additional sandbox settings
• Performance improvements for long-running servers
• B42 servers are not backward-compatible with B41 saves – upgrading requires a fresh world

Zombies are the core antagonists of Project Zomboid, and the game gives us a sandbox toolbox to shape them to our liking. This section will cover how to adjust zombie population, their abilities (speed, strength, etc.), and related systems to dial in the challenge.

2.1 The "Zombie Lore" Settings

"Zombie Lore" refers to the set of options that define what zombies are like in your world. In the server SandboxVars, these are grouped under ZombieLore = { ... }.

2.2 Population and Respawn

The Advanced Zombie Options determine the zombie population distribution across the map, how it grows over time, and if (and how) zombies respawn in cleared areas.

CPU/Network Impact: The number of zombies active around players is a big factor in server load. If you have 10 players each in different towns with high population, that's many zombies active at once. Some server admins reported that beyond ~2000 active zombies in a cell, the server might start struggling. For detailed server performance optimization, see our server administration guide.

2.3 Special Events and Meta-Game Settings

Project Zomboid has a "Sadistic AI Director" that controls meta-events – notably the Helicopter Event. By default, about 1 week in, a random helicopter shows up and buzzes around, attracting every zombie for miles to your position.

On a multiplayer server, especially PvE, the heli can be chaos: it'll attract a massive migrating horde that could flatten smaller bases or overwhelm new players. Many PvE server hosts choose to turn off the helicopter meta-event entirely.

SandboxVars = {
    Zombies = 4, -- 4 = "Insane" population (4x default)
    PopulationMultiplier = 4.0, -- explicit same as above
    PopulationPeakMultiplier = 4.0, 
    PopulationPeakDay = 14, -- reach peak in 2 weeks (fast ramp-up)
    RespawnHours = 48, -- respawn check every 2 days
    RespawnUnseenHours = 24, -- a full day unseen needed to respawn
    RespawnMultiplier = 0.1, -- 10% of zombies respawn per cycle
    ZombieLore = {
        Speed = 1,        -- 1 = Sprinters (fast!)
        Strength = 3,     -- 3 = Weak (balances sprinters a bit)
        Toughness = 3,    -- 3 = Fragile (easy to kill if you can hit them)
        Transmission = 1, -- 1 = Blood+Saliva (standard infection)
        Mortality = 4,    -- 4 = 0–12 hours (if infected, you turn within half a day)
        Reanimate = 2,    -- 2 = 0–1 minutes to reanimate
        Cognition = 3,    -- basic cognition (they open doors or not)
        Sight = 2,        -- 2 = Normal sight
        Hearing = 2,      -- 2 = Normal hearing
        Memory = 3,       -- 3 = Long memory (they remember longer)
    }
}

Tuning loot is vital: too scarce and your players may starve or get frustrated, too abundant and the survival aspect diminishes quickly. This section also covers things like item cleanup and nature progression which impact server performance and gameplay.

3.1 Loot Rarity and Item Respawn

In sandbox settings, loot rarity can be set for different categories, typically: Food, Weapons, Other (Misc) and possibly specific ones like Medical or Survival Gear.

Default: In a vanilla server, loot respawn is typically off (so the world is one-and-done, what's looted stays looted). The reasoning is realism and to encourage travel. But on populated servers, you'll find towns near spawn get completely stripped within days.

3.2 World Decay, Item Cleanup, and Time Progression

The apocalypse isn't just about zombies and loot – the world itself changes over time. Two important aspects:

• Erosion (Nature taking over): Controls how fast vines grow, grass cracks through roads, etc. Default is 100 days to full erosion.
• Blood and Corpses Cleanup: Project Zomboid by default does not auto-remove corpses or blood unless configured. Piles of corpses can cause FPS drops.

In server settings, you have HoursForCorpseRemoval which controls after how many in-game hours corpse bodies disappear. There's also HoursForWorldItemRemoval for general items like clothing.

Project Zomboid servers generally fall into two categories: PvE (Player vs Environment) where cooperation is key and players don't harm each other, and PvP (Player vs Player) where all bets are off – you're as likely to be killed by a rival survivor as a zombie.

4.1 Enabling or Disabling PvP

The most straightforward switch is in servertest.ini: PVP=true or false. This globally turns on or off the ability to hurt other players.

• SafetySystem (true/false): If enabled, players have a little skull icon that toggles PvP mode. Only when one player is PvP-enabled can they hurt others.
• Safety cooldowns: Settings SafetyToggleTimer and SafetyCooldownTimer control how long it takes to toggle PvP on/off, and the cooldown between toggles.
• ShowSafety: If true, the skull icon above players' heads shows when they are PvP-active.

4.2 Factions – Friend or Foe Identifier

On PvP servers, factions become quite important. A faction in PZ is basically a group of players who have formally joined together via the game's interface. The benefits:

• You can see your faction members' names by default and on the player overlay map
• You can disable friendly fire within faction (prevents accidental team damage)
• Factions have a chat channel (if global chat is off, faction chat allows coordination)

For more details on PvP mechanics and the skull icon that appears next to player names, see our PvP skull icon guide.

Faction settings in servertest.ini:

• Faction=true/false toggles whether players can create factions at all
• FactionDaySurvivedToCreate=0 by default. You can require players to have survived X days before creating a faction
• FactionPlayersRequiredForTag=1. This determines when a faction gets a tag (like a label prefix on names)

PVP=true
GlobalChat=false         # local chat only for realism
SafetySystem=true
ShowSafety=true
SafetyToggleTimer=5
SafetyCooldownTimer=30
NoFire=false             # allow fire (dangerous weapon!)
PlayerSafehouse=true
SafehouseAllowTrespass=true   # raiders can enter
SafehouseAllowLoot=false      # but cannot loot unless base is "open"
SafehouseAllowFire=true       # fire can damage safehouse
SafehouseAllowRespawn=false   # no free respawn at base
SafeHouseRemovalTime=144      # 6 days offline = base unclaimed
DisableSafehouseWhenPlayerConnected=true  # base raidable when online
Faction=true
FactionPlayersRequiredForTag=2  # need 2 members for tag

Project Zomboid's multiplayer isn't just about surviving against zombies – it's also about forming communities (or rivalries) among players. The Safehouse and Faction features are the game's built-in tools to facilitate this.

5.1 Safehouses – Your Home in Knox County

A safehouse in PZ is a claimed building (or area) that grants certain protections and privileges to its owner and members:

• Only the owner (and invited players) can open doors/windows, loot containers, and sleep there
• It can serve as a spawn point (if allowed) for its members
• It is marked on the map for members, making navigation easy

5.2 Safehouse Settings Recap

5.3 Factions – Strength in Numbers

While safehouses are about where you live, factions are about who you run with. In PZ, factions add a lot of social dynamic. For detailed base building and fortification strategies, check out our complete base building guide:

• A player can create a faction via the user panel – they choose a name and a 3-letter tag
• Faction members can see each other's health status and location on the map
• By default, faction members cannot hurt each other even if PvP is on

Don't forget to utilize out-of-game platforms like Discord alongside these in-game features. Most successful servers have a Discord where factions have their own channels, safehouse screenshots are shared, etc.

Even in an apocalypse, someone's gotta enforce the rules (or fix the bugs) – that's you, the server admin. This section covers the tools at your disposal to manage your Project Zomboid server, from commands to configurations.

6.1 Whitelisting and Account Management

Open vs Whitelisted Servers: In servertest.ini, Open=true means anyone can join without being pre-added to a whitelist. Open=false means you're running a closed server – you must manually add each player's username to the whitelist.

If you do whitelist mode, you'll get familiar with commands:

• /adduser Username Password – adds a new whitelist entry
• /removeuser Username – to remove from whitelist
• /grantadmin Username – to give a user admin privileges

6.2 Admin Commands and In-Game Tools

As admin, when you're in-game on your admin account, you have a few superpowers:

• Press Home key (by default) to open the Admin Panel
• Toggle invisibility and god mode on yourself
• Use the Sandbox Options tab to live-adjust certain settings
• Item spawn / creative mode: Admins can spawn any item
• Teleport and coordinates: You can teleport yourself or other players

6.3 Remote Admin (RCON) and Discord Integration

Sometimes you can't be in-game but need to administrate. That's where RCON (Remote Console) comes in:

• Enable by setting RCONPort (pick a port like 27015) and RCONPassword to something secure
• Use an RCON client to connect and issue commands remotely
• Build 42 is introducing a direct Discord integration feature that allows the server to send messages to a Discord channel

6.4 Common Issues and Troubleshooting

Even well-run servers hit snags. Here are a few frequent ones and how to handle them:

• Can't Connect / Stuck at "Connecting": This could be ports not open (check that 16261 and 16262+ are open), or a version mismatch (client hasn't updated to same version as server), or a mod mismatch.
• Lag/Desync Complaints: If multiple players get lag at times, check your CPU/RAM usage on host. If CPU is maxing out often, reduce zombies or player count.
• Server Crash: Usually you'd see an error in console/log. Could be a mod error (often a NullPointer or Lua error referencing a mod file).

Mods can hugely enrich Project Zomboid's experience – from adding new weapons and vehicles, to total conversion gameplay changes, to handy admin tools. But mods also bring complexity and potential instability.

7.1 Installing and Enabling Mods on a Server

Project Zomboid uses the Steam Workshop for most mods, which makes life easier:

1. Find the mod(s) you want on Steam Workshop and note both the Workshop ID and the Mod ID
2. Subscribe to them on the server's Steam account
3. In servertest.ini, set WorkshopItems=<list of Workshop IDs> and Mods=<list of Mod IDs>
4. When the server starts, it will auto-download those Workshop items if not present

WorkshopItems=2169435993;2392709985
Mods=TSARasteroids;AlicePackMod

7.2 Popular Mods and Their Considerations

Some mods become so popular that many servers treat them as quasi-essential. Here are a few categories and examples:

• Maps & Map Expansions: "Pitstop", "Raven Creek", "Fort Redstone", "Blackwood", etc. These add new towns or areas to the vanilla map. They tend to be big downloads and use a lot of memory.
• Weapons & Gear: "Brita's Weapon Pack" (very popular gun mod), "Swat Pack", etc. These can dramatically alter gameplay.
• Vehicles: "Filibuster Rhymes' Used Cars (FRUC)" – adds tons of vehicles. Great for variety, but can impact performance if players hoard cars.
• UI/Quality of Life: "Authentic Z" (cosmetic clothing), "Better Sorting" (inventory categories), "Skill Recovery Journal" (recover XP after death).
• Total Overhauls: Mods that completely change game meta, like adding NPCs ("Superb Survivors" or "KI5 NPCs").

7.3 The Cost of Mods – Performance and Administration

As mentioned, more mods generally means:

• More assets to load (players with slower PCs or limited bandwidth might struggle)
• More things that can go wrong (each update is a potential new bug)
• More memory usage on server (especially maps and item-heavy mods)
• Possibly more save file size – every new item placed in the world adds to save data

7.4 Vanilla Server Merits

It's worth noting that vanilla (no mods) servers have their perks:

• Max stability – only base game bugs to worry about
• Easy for new players – no downloads, no learning mod content
• When game updates, you can update immediately with no mod compatibility wait

Lag and downtime are the real zombies that can kill your server population if not managed. This section covers hardware needs, network tips, and troubleshooting latency or resource issues.

8.1 Server Hardware and Slots – Knowing Your Limits

Official Requirements: Experience from community suggests:

• CPU: Aim for high single-core performance. A 3+ GHz modern CPU core is recommended.
• RAM: For Build 41, 2–3 GB was enough for a small server (up to ~8 players). With lots of mods or a full 32 players, you'll want 6–8 GB or more.
• Bandwidth: PZ isn't extremely heavy per player – maybe on the order of tens of KB/s per player under normal conditions.

Max Players (Slots): The engine caps at 32 by default. You can hack it for more but not advised – it likely won't handle it well.

8.2 Monitoring Performance and Logs

Keep an eye on:

• Server console (if you have access): It prints useful info like players connecting, errors, and periodic stats
• Logs/ directory: especially console.txt (server log) and chat.txt (if enabled)
• Memory usage: If creeping high (like within 500MB of your max allocated), might be a leak – restart the server daily

8.3 Network and Latency: Fine-tuning

Project Zomboid allows both direct IP join and Steam-based join. Steam networking can handle NAT punch-through often even if you didn't forward ports – but it's not foolproof. I recommend doing proper port forwarding if hosting yourself:

• Required Ports: 16261 UDP and 16262-<16262+Slots> UDP (each player after the first uses an incremented port)
• Server Location: Choose a location geographically central to your player base. Ping matters.

8.4 Maintenance and Wipes

We discussed backups and resets – it's part of performance in the long run:

• If your world has been running for 6+ months real-time, the map might be very looted and cluttered. You might plan a "Season 2" wipe to refresh interest and performance.
• Let players know how long a season will roughly last if you can estimate. Some servers advertise "no wipe unless forced by update".
• Clean up unused log files – not an in-game perf issue, but disk space.

8.5 The Human Factor – Keeping Players Happy

A smooth server is not just about code, but how responsive you are:

• If players report lag, acknowledge it and say you'll investigate – even that helps them be patient.
• Post announcements if you need to reboot ("Server restart in 5 minutes for maintenance").
• Provide avenues for players to report performance issues, like a Discord channel.

Running a Project Zomboid server is part science, part art. You've got the science in this guide: all the nitty-gritty settings from Build 41 and 42 that you can tweak, and the technical tips to keep lag at bay. The art comes in how you mix those settings to craft a particular experience – be it a chill PvE haven where players build farms and recount stories around a campfire, or a brutal PvP landscape of ambushes and last stands, or perhaps a roleplay community with its own economy and laws.

As a seasoned survivor (and server admin), my last advice is: listen to your players and to the server itself. If the zombies are too easy, you'll hear it (or see players getting complacent) – crank it up a notch. If the server hardware groans under a mod, maybe trim it or upgrade resources. Don't be afraid to iterate.

Project Zomboid's Build 41 and 42 have given us a robust framework and many new toys (animals, improved MP, mod support). With this guide, you're well-equipped to harness them. So get out there, tweak those ini files, adjust those zombie spawn rates, install that shiny mod (or ten), and most importantly, have fun with it. A well-run server becomes more than just a game – it becomes a little story generator for everyone involved.

Good luck, and may your server thrive in the Knox Event! Now, if you'll excuse me, I hear the telltale whir of a helicopter approaching in my own server… time to see how my settings truly held up. Stay safe, survivors.