If you've been running your own ATLAS cluster or a single-grid server at home or on another host, and you want to move the whole thing over to LOW.MS without losing ships, characters, companies, or territory, this guide walks you through it. ATLAS doesn't really have a singleplayer worth talking about, so almost every migration is server-to-server. The good news is that once you know which folders matter, the upload itself is straightforward.
Where ATLAS Saves Live on Your Server
On any ATLAS dedicated server — yours, your old host's, or a box in your cupboard — the save data sits inside the install under:
ShooterGame\Saved\
The important paths inside Saved\ are:
Saved\SavedAtlasLocal\orSaved\<GridLetter><GridNumber>\— the actual world data for that grid. Inside you'll mostly seeocean_X_Y.atlasfiles (one per grid tile), plus profile and tribe data files that hold companies, characters, and tames.Saved\Config\WindowsServer\— yourGameUserSettings.iniandGame.ini, which hold rates, rules, and admin passwords.Saved\SavedArks\— per-grid world state snapshots on some setups.
Outside Saved\, there are three cluster files that also need to come with you, and these live directly inside ShooterGame\:
ShooterGame\ServerGrid.json— the full definition of your world: grid size, islands, discovery zones, spawn regions.ShooterGame\ServerGrid.ServerOnly.json— the per-server routing table (IPs, ports, database host, database password).ShooterGame\ServerGrid\— the map image tiles players see when they open their in-game map.
If you skip any of those three, the grid will either refuse to boot, revert to a default map, or show a blank compass.
Before You Do Anything
Stop the old server fully before you copy anything. ATLAS writes on a timer and on shutdown, so grabbing files from a running server will give you a half-written world.
On the LOW.MS side, log into control.low.ms, open your new ATLAS service, and take a Cloud Backup first. That gives you a clean rollback point if the upload goes sideways. Then stop the server from the panel — don't upload over a running process.
Zip your old server's ShooterGame\Saved\ folder and the three ServerGrid* items together on your local machine. One archive per grid is easiest to track.
Uploading via File Manager
For a single grid or a small cluster, the browser-based File Manager is fine.
- In control.low.ms, open the ATLAS service and click File Manager.
- Navigate to
ShooterGame\. - Upload your
ServerGrid.json,ServerGrid.ServerOnly.json, and theServerGrid\folder (tiles) intoShooterGame\, overwriting what's there. - Open
Saved\and upload your oldSaved\contents in, replacing the fresh ones. - If you uploaded a
.zip, use the right-click extract option rather than downloading and re-uploading.
File Manager has upload size limits per file, so anything over a couple of GB — a mature cluster with months of data — should go via SFTP instead.
Uploading via SFTP
SFTP is the right tool for big worlds and multi-grid clusters.
- In control.low.ms, open Service Settings and grab your SFTP host, username, and password.
- Connect on port 8822 using FileZilla, WinSCP, or any SFTP client.
- On the remote side, browse to
ShooterGame\. - Drag your
ServerGrid.json,ServerGrid.ServerOnly.json,ServerGrid\folder, and the fullSaved\folder across. Let the client overwrite existing files. - Wait for the transfer to finish completely before touching the panel again — a restart mid-transfer will corrupt the save.
Pointing the Server at Your World
ATLAS cares about coordinates. Each grid process needs to know which cell of the world it is serving. In ServerGrid.ServerOnly.json, every grid has its own entry with gridX, gridY, MachineIdTag, IP, Port, GamePort, and SeamlessDataPort.
Update the IP field for each grid to the IP of its LOW.MS service, and make sure the ports match what LOW.MS has allocated (visible under Service Settings). The database host and password entries need to point at whichever grid you've chosen as the master. Every single grid in the cluster must have an identical copy of ServerGrid.json and ServerGrid.ServerOnly.json — mismatches here are the single most common cause of failed seamless travel.
Starting Up
Open the Web Console on each grid, then start the server from the panel. The first boot on a migrated world takes longer than usual — it's loading a populated world, not a fresh seed. Watch the console until you see the server report its grid name and say it's ready for connections.
Connect in game and check: your character exists, your company roster is intact, ships are where you parked them, and sailing across a grid border triggers a seamless transition rather than a disconnect. If the map shows up blank, the ServerGrid\ tile folder didn't upload. If travel fails, re-check the grid's ServerGrid.ServerOnly.json against the master copy.
A Few Things to Know
ATLAS clusters are harder than ARK. Every grid is its own server process, every process reads the same two JSON files, and they all need to agree on the cluster's database host. Edit those JSON files in ServerGridEditor (Grapeshot's official tool) rather than by hand — a stray comma will stop the cluster loading.
If something goes wrong, use Cloud Restore to roll back to the pre-upload backup and try again. For game binaries and updates, use Steam Update from the panel — never overwrite ATLAS's installed files with your local copy, only the Saved\ and ServerGrid* data.
Open a ticket if you're moving more than four grids or a very large world, and the team will help plan the cutover window.