Icarus Server Hosting

What is an Icarus dedicated server, and why rent one?

The Icarus dedicated server is RocketWerkz's official software for running co-op sessions independently of players' PCs. It is a separate tool on Steam, downloaded with SteamCMD using app_update 2089300. Installation, launch parameters, prospect transfer and admin commands are documented on RocketWerkz's official GitHub wiki.

Icarus is played through mission sessions called “prospects” or a persistent open world. In a session hosted on a player's PC everyone drops when the host leaves; a dedicated server keeps the session up, lets friends join at different times and frees the host's PC from carrying both graphics and server load.

A dedicated server makes the biggest difference in long open-world games and prospects that span several weeks: your base, crops and inventory are kept safely in one place. For a group connecting from Türkiye, a server in a nearby data center reduces the lag you feel while fighting creatures and building. Icarus's 8-player limit usually makes the server a shared space for a small, closed group of friends, so passwords, admin rights and backups should be set up properly from the start.

How much RAM and CPU does an Icarus server need?

RocketWerkz doesn't publish fixed hardware requirements for the dedicated server on its official wiki; the table above is an estimate based on the game's Unreal Engine foundation and its 8-player sessions. Icarus simulates a large map, weather events, creature AI and player structures, so it needs more memory than many light co-op games with the same player count.

• Game mode: a short prospect and an open-world session lasting months create very different loads. Large bases and many placed objects increase memory use.
• CPU: creature AI and world events such as storms cause CPU spikes. Dedicated cores reduce stutter at these moments.
• Disk: server files are large and grow with updates; leave room for saves and backups. NVMe storage shortens load times.
• Windows overhead: Windows Server itself uses memory; read the table with that in mind.

Watch memory use in the first weeks. On Windows Server use the Performance tab of Task Manager or Resource Monitor. If the IcarusServer process grows during a session and drops after a scheduled restart, that's normal; if it quickly hits the limit again after a restart, the server genuinely needs more resources. Base the decision on several days of observation, not one busy evening.

Should you choose a ready-made package or a VDS for Icarus?

This page shows VDS packages for Icarus: you can install the server yourself or request a ready-made setup through a support ticket. Since the official guide is written for Windows, using your VDS with Windows Server is the path with fewest surprises; you connect over Remote Desktop, run SteamCMD and manage the server just like on your own PC.

• Cores and memory are reserved for you, so performance during storms or heavy combat isn't affected by neighbouring loads.
• You have full control over ServerSettings.ini, launch parameters and the save folder.
• You can run a second instance on different ports to try a new mission without disturbing your main prospect.

For Windows Server licensing see operating system licenses. For a detailed comparison see game server package or VDS. Choose from the live package table to fit your player count and game mode; resources can be increased later. You can also host a Discord bot, voice server or another game on the same VDS, as long as you budget memory separately for each and leave Icarus the values in the table.

Which settings are in ServerSettings.ini?

ServerSettings.ini controls how the Icarus server behaves; according to the official wiki it lives in the Saved\Config\WindowsServer\ folder. The Saved folder is created under %localappdata%\Icarus\ by default and can be moved with the -UserDir= parameter.

The official wiki notes that the SessionName field currently doesn't work and recommends setting the server-list name with the -SteamServerName= launch parameter. Shut the server down before editing the file.

Why does an Icarus server shut down when empty, and how do you keep it up 24/7?

With default settings an Icarus server shuts itself down within 300 seconds if nobody joins or after the last player leaves; this is the most common reason for “my server has stopped” on rented servers. According to the official wiki, ShutdownIfNotJoinedFor and ShutdownIfEmptyFor are in seconds: 0 means shut down as soon as possible, and a negative value means run indefinitely.

To keep your server reachable 24/7, set both to a negative value:

ShutdownIfNotJoinedFor=-1
ShutdownIfEmptyFor=-1

The server then keeps running and consuming resources while empty, which is usually what you want for open-world sessions. Alternatively, let it shut down and have a Windows service or scheduled task restart it, though players may then have to wait for it to come back when they want to join.

Because ResumeProspect is on by default, the server continues the last prospect after a restart. A scheduled restart also refreshes memory on long-running servers; put it at the quietest hour.

How do you secure admin rights on an Icarus server?

Admin security on an Icarus server depends entirely on the AdminPassword setting, and leaving it empty is a serious risk. According to the official wiki, if AdminPassword is empty, the in-game /AdminLogin command grants admin rights to any player. On a public or password-less server that means the first player to arrive can manage prospects and kick others.

1. Set a long, unguessable AdminPassword and share it only with admins.
2. Set a JoinPassword if you want the server closed to outsiders.
3. Disable AllowNonAdminsToLaunchProspects to leave new prospects to admins, so no one changes the active mission by accident.
4. Keep the list of people who use admin commands short.

The “Console RCON Commands” page on RocketWerkz's wiki lists the admin commands. Backing up the prospect before using them is the only safe way to undo a wrong command. Remember that passwords are stored in plain text: anyone with access to ServerSettings.ini can read the admin password. Don't share Remote Desktop accounts, create a separate Windows user for each admin and change AdminPassword when an admin leaves the team.

How do you move a local prospect to the server?

An Icarus prospect started on your own PC can be moved to a dedicated server using the method on the official wiki; a prospect is stored as a single JSON file.

1. Back up: the wiki warns that renaming the file or editing its JSON can corrupt the save permanently. Keep a copy first.
2. Find the local file: the prospect file in %UserProfile%\AppData\Local\Icarus\Saved\PlayerData\{SteamID}\Prospects\.
3. Create the target folder: if Icarus\Saved\PlayerData\DedicatedServer\Prospects doesn't exist in the server install, create it.
4. Copy the file: copy the prospect file into this folder without renaming it.
5. Load it: put the prospect name in LoadProspect or load it from the lobby.

Use Remote Desktop clipboard and drive sharing or another secure transfer method. After moving, connect and check your base, inventory and mission state; if something is wrong you can return to the backup.

How do prospects and open-world sessions affect the server?

The session type you run decides both how the server is managed and how many resources it needs. Classic prospects are bound to a goal and a time limit; when the mission ends or time runs out players return to orbit. Open-world sessions are indefinite; bases grow, crops and storage pile up and the world stays the same for weeks or months.

The official wiki offers three settings for the startup session. ResumeProspect continues the last session and is on by default. LoadProspect loads a named save. CreateProspect creates a new session from values in the form [ProspectType] [Difficulty] [Hardcore?] [SaveName]; prospect type names are listed on the wiki's “Prospect Names” page.

For a long-running open world: run with ResumeProspect on, set shutdown times to a negative value and back up the save daily. For a mission-focused group AllowNonAdminsToLaunchProspects can stay on so players pick the next mission from the lobby. Either way, a growing open-world save increases memory and disk needs over time.

How do you update an Icarus server?

The Icarus server is updated with SteamCMD: stop the server, back up the prospect files and run app_update 2089300 validate again. Players' Steam clients update automatically, so a server left behind is a frequent cause of “server not visible” or “can't connect” problems. RocketWerkz's wiki has a separate page on updating and running the server.

• Put the SteamCMD commands in a batch file (.bat) so updating is one click.
• Take a dated copy of the prospect folder before updating.
• Watch the server for a while after big content updates and tell players if the logs show errors.
• If the server runs as a Windows service or scheduled task, pause automatic restarts during the update.

Store backups off the server. Update when the fewest players are online and post a short notice to your community beforehand.

How is an Icarus server protected against DDoS and unauthorised access?

A public Icarus server is exposed to denial-of-service attacks because its IP appears in the Steam server list, so protection must cover both network and server. On LIONFIN infrastructure traffic is filtered at network level by the RouteFence firewall, DDoS traffic is filtered before it reaches your server where possible, and everything is monitored 24/7 by our NOC and SOC (see our data center).

• Firewall: open only the game port (17777) and query port (27015); keep other inbound connections closed.
• Remote Desktop: don't leave RDP open to everyone on the default port; use a strong password and IP restrictions.
• Passwords: set AdminPassword and, if needed, JoinPassword, and keep them different.
• Updates: apply Windows security updates regularly and schedule restarts outside play hours.

Signs of an attack include all players disconnecting at once or the server dropping off the list; in that case open a support ticket from the customer panel to have the network side checked. If only one player drops, it is usually that player's home connection, so note the times and the players affected.

Does the Icarus server run on Linux?

RocketWerkz's official guide is written for Windows and the server ships as a Windows application, IcarusServer.exe; the official docs don't mention a native Linux build. The community has found ways to run it on Linux with Wine or Wine-based Docker images, and some hosting companies use this approach.

• Pro: Linux needs no Windows Server licence and the OS uses less memory.
• Con: the Wine layer isn't officially supported; game updates can cause unexpected errors and troubleshooting is harder. File paths in the official wiki are written for Windows too.

For a long-running open-world server where stability matters, we recommend Windows Server. If you have Linux and Wine experience and resource efficiency is your priority, Linux can work; in that case test on a staging server before moving your main prospect.

What are the most common Icarus server problems?

Most Icarus server problems come from shutdown settings, ports or version mismatches; the server logs usually show the cause clearly.

• The server shuts down after a few minutes: ShutdownIfNotJoinedFor and ShutdownIfEmptyFor are at the default 300 seconds. Use a negative value for a 24/7 server.
• Not visible in the server list: query port 27015 is closed, or the server has only just started. Check the port rules.
• Server name doesn't show: the name was set with SessionName, which the official wiki says currently doesn't work; use -SteamServerName=.
• Anyone can become admin: AdminPassword is empty.
• A moved prospect won't load: the file was renamed or copied to the wrong folder; check the PlayerData\DedicatedServer\Prospects path.
• Version mismatch: the server hasn't been updated; update it with SteamCMD.
• A ninth player can't join: an Icarus server takes at most 8 players; this is a limit, not a bug.

If you get stuck, open a support ticket from the customer panel with the logs attached.