How to Update Your Minecraft Server
Where Minecraft updates happen on GameGrid, what the platform does during one, and how to run your own jar instead.
Before You Update
1. Take a manual backup from the Backups tab - "Create Backup Now", with a label so you can find it. This is your only way back if the update breaks something.
2. Check your plugins or mods support the new Minecraft version. Each one's page on CurseForge, Modrinth or Hangar lists what it supports.
3. On a modded server, update the loader and every mod together. A half-updated mods/ folder usually will not start.
4. Tell your players. They have to be on the same version to connect.
Where Updating Happens
The Admin tab, in the card called Game Updates. There is no version selector in Settings - that is worth saying plainly, because it is the thing people go looking for.
The card names the build your server is running. If it says the build has not been reported yet, the host has not checked in since; it fills in on the next check-in.
"Automatically apply game updates" is a switch. With it on, a new build is applied for you when one is detected.
When a new build is available you get an "Update available" badge with the version, and an "Update now" button that applies it immediately whether or not the switch is on.
Restarting the server does not update it. A restart relaunches the files already on the host.
What Happens During an Update
The platform backs your server up, warns anyone playing, stops the server, moves it onto the new build and starts it again.
Players are warned in game with a countdown, beginning five minutes out. The countdown is a courtesy - the update proceeds at the end of it either way.
An empty server is updated immediately with no countdown.
The card is rewritten with the real outcome when the work finishes, including the exact error text if it fails, and the platform rolls back to the previous build if the new one will not come up.
Running Your Own Jar
Settings has a "Server JAR File" dropdown. It lists the .jar files present in your server directory, and it decides which one the server launches.
Upload a jar through the Files tab or over SFTP and it appears in that dropdown. That is how you pin a specific Paper build, or run a jar the platform does not ship.
The setting is restart-required, so saving it restarts your server for you.
This is a manual arrangement. A jar you selected yourself is yours to keep current - platform updates will not manage it for you, and a mismatch between your jar and your world is your responsibility.
Forge and NeoForge servers do not launch from a jar when their installer has been run; they launch from user_jvm_args.txt plus the loader's own argument file. The dropdown is only a fallback there.
Updating Plugins and Mods
After the server version changes, update everything in plugins/ or mods/ to builds for the new version.
From the Mods tab, the marketplace search is scoped to your server type, so what it offers is already the right kind of build. Remove the old one from the Installed view and install the new.
By hand: stop the server, replace the .jar in the Files tab, start the server.
A plugin or mod that loads is not necessarily working. Check the Console tab after the first start, and test the features you care about.
If Something Goes Wrong
Restore the backup you took, from the Backups tab. The platform stops the server, restores and starts it again, and takes a copy of the current state first so the restore is itself reversible.
Never try to run a world on an older Minecraft version than it has already been loaded on. Minecraft upgrades world data one way; going back corrupts it. Restore a backup instead. See Can You Downgrade a Minecraft Server?.
If the server will not start at all, the Console tab has the first error and logs/latest.log in the Files tab has the full output. Attach that to a ticket.