Valheim Dedicated Server Settings and Command Generator

Valheim's dedicated server is configured with launch arguments. The generator below produces a Windows or Linux launch line from options documented by Iron Gate. It runs entirely in this page, stores nothing, and does not transmit the server name, path, or password.

valheim_server.exe -nographics -batchmode -name "My Valheim Server" -port 2456 -world "Dedicated" -password "change-me-123" -public 1 -saveinterval 1800 -backups 4 -backupshort 7200 -backuplong 43200 -crossplay

Review before use. Keep a copy of the original launch script, compare generated arguments with the server manual distributed with the current dedicated-server application, and test against a backed-up world. Never commit a real password to source control.

Core server settings

Values containing spaces need plain straight quotation marks. Avoid typographic quotes copied from formatted documents.

Windows and Linux executable names

The arguments are shared, but the executable wrapper differs:

valheim_server.exe -nographics -batchmode [arguments]

./valheim_server.x86_64 -nographics -batchmode [arguments]

Use the supplied start_headless_server.bat on Windows or start_server.sh on Linux as the current reference. Iron Gate recommends editing a copy because Steam updates can reset the supplied original.

Server name, world name, and password

These three values are related but not interchangeable:

• -name controls what players see in the server browser;
• -world controls which world the server creates or loads;
• -password protects joining and should remain private.

Changing the visible server name does not rename the world. Changing -world can load a different existing world or create one when the requested world cannot be found. Before changing it, confirm the active save location and create a world backup.

The generator deliberately accepts a restricted character set so that its output cannot contain obvious batch or shell control characters. If the production configuration needs other characters, edit manually and review the escaping rules for that operating system.

Ports

Valheim uses the selected base port and the next port. The documented default base is 2456, which means 2456-2457.

For the Steam backend, the range must be reachable from the internet for outside players. That normally involves the host firewall and router forwarding.

With PlayFab crossplay, outside traffic uses a relay and does not require port forwarding. The port still distinguishes multiple servers sharing a public address.

When running multiple instances, assign each one:

• a unique port range;
• a unique world name;
• a separate save directory;
• a separate launch script and log;
• a unique -instanceid when Iron Gate's documented PlayFab condition applies.

Never run two server processes against the same writable world data.

Public versus hidden servers

Use:

-public 1

to make the server visible in the public browser, or:

-public 0

to hide it. A hidden server can still be reachable through an appropriate direct method, but it will not appear merely because the process is online.

If a public server does not appear, confirm that it reached Game server connected, then use the server-not-showing guide.

Steam or PlayFab crossplay

PlayFab supports public address and port, join code, and server-list connections. It does not support local or loopback connections. Use the crossplay guide before switching a production community.

Save directory

The official default save roots are:

-savedir overrides the default. An explicit production directory can make migration and backup checks clearer, but moving it is a data migration—not merely a launch-line edit.

Before changing -savedir:

1. stop the server with CTRL+C;
2. back up the current active location;
3. copy the complete required data to the new location;
4. confirm the server account can write there;
5. update the launch line;
6. verify the world, permission lists, save, and restart behavior;
7. preserve the old directory until the move is accepted.

Save and automatic backup settings

Shorter save intervals reduce potential progress loss but increase write frequency. More automatic backups increase recovery coverage but still remain on the live server environment. Maintain a separate manual or off-machine backup policy.

World presets

Iron Gate currently documents these preset names:

• Normal
• Casual
• Easy
• Hard
• Hardcore
• Immersive
• Hammer

The launch pattern is:

-preset hard

A preset overwrites previous modifiers. When combining a preset with a specific modifier, place the individual modifier after the preset so the intended override is explicit.

Individual modifiers

The current server guide documents modifier categories for combat, death penalty, resources, raids, and portals. The syntax is:

-modifier raids none

Documented values include:

Use the spelling from the current server manual. Do not invent combinations based on the in-game label alone.

World keys

Iron Gate currently documents these -setkey values:

• nobuildcost
• playerevents
• passivemobs
• nomap

Example:

-setkey nomap

Some world modifiers affect achievement eligibility in Valheim 1.0. The 1.0 FAQ specifically identifies Hammer mode as a temporary cheat state. Review achievement implications before applying modifiers to a long-term achievement-focused world.

Administrator, banned, and permitted lists

The active save location includes:

• adminlist.txt;
• bannedlist.txt;
• permittedlist.txt.

Add one case-sensitive Platform User ID per line. Iron Gate notes that using permittedlist.txt excludes everyone who is not listed. Obtain Platform User IDs from the server log or the in-game F2 panel.

These files follow the active save location. If -savedir changes, verify that the intended permission files moved with the world.

Configuration review checklist

• The supplied launch script was copied before editing.
• Server name and world name serve the intended separate purposes.
• The password is private and absent from source control.
• The base port and port +1 do not conflict with another instance.
• Steam or PlayFab crossplay was selected deliberately.
• -public matches the intended discovery method.
• -savedir points to a backed-up, writable location.
• Save and backup retention values are explicit.
• Presets appear before individual modifier overrides.
• Achievement implications were reviewed.
• The line was compared with the current distributed server manual.
• The server reaches Game server connected and survives a save/restart test.

Official sources

• Valheim dedicated-server guide
• Valheim crossplay FAQ
• Valheim 1.0 FAQ

Next: set up the dedicated server, back up the world, or troubleshoot a connection.