> ## Documentation Index
> Fetch the complete documentation index at: https://simplecloud.app/docs/llms.txt
> Use this file to discover all available pages before exploring further.
# Server Groups
> Create a group of Minecraft servers and configure how it scales.
A server group creates replaceable servers from one shared configuration. Use a group when you want several identical servers or want SimpleCloud to adjust the number of servers for you.
| Use a group for | Use a persistent server for |
| ---------------------------------------- | ------------------------------------------------------ |
| Proxies, lobbies, and minigames | SMP, Citybuild, and build servers |
| Servers that can be replaced at any time | A server that must keep its world or other local files |
| Several servers with the same setup | One long-running server |
See [Persistent Servers](/docs/en/manual/setup/persistent-servers) if the right-hand column matches what you are creating.
Before you start, [connect at least one serverhost](/docs/en/manual/setup/installation) to your network.
## Choose a group type
| Type | Choose it for | Examples |
| ---------- | ------------------------------------------ | ----------------------------- |
| **Server** | Game servers that players join | Paper, Purpur, Spigot, Fabric |
| **Proxy** | Proxies that route players to game servers | Velocity, BungeeCord |
## Create a server group
In the dashboard, open **Server Groups** and click **Add Group**.
Choose **Server** or **Proxy**, then enter a unique name. Names may contain up to 100 ASCII letters, digits, underscores, and hyphens (`[A-Za-z0-9_-]`) and are unique within the network case-insensitively — `Lobby` and `lobby` count as the same name.
Enable **Activate on creation** if SimpleCloud should start the group immediately.
Select the server software and the available version options.
If the software is not listed, choose **Custom** and fill in the required fields.
Choose the player limit and memory for each server. Make sure your serverhosts have enough memory for the number of servers you plan to run.
For a proxy group, also enter its starting port.
Review the configuration, add any plugins you need, and click **Create Group**.
## Activate or deactivate a group
An active group starts and stops servers to meet its scaling configuration. An inactive group does not run any servers.
**Activate on creation** is enabled by default. After creating the group, open its **Servers** tab to follow the first server as it starts. You can activate or deactivate the group later from its action menu.
## Configure scaling
Scaling controls how many servers SimpleCloud keeps ready. Open the group, then go to **Settings > Scaling**.
Both modes use these limits:
* **Minimum Servers** is the baseline number of servers the group keeps running.
* **Maximum Servers** is the most servers the group may run.
Then choose the mode that matches how you want the group to grow.
### Scale by player slots
Choose **Slots** when SimpleCloud should adjust the number of servers according to player capacity. Set **Available Slots** to the number of free player spaces you want to keep across the group.
SimpleCloud starts servers when more capacity is needed and stops unused servers when enough capacity remains. It always stays between your minimum and maximum.
For example, if each server allows 100 players and **Available Slots** is `50`, SimpleCloud starts another server when the group has fewer than 50 free player spaces.
**Idle Time** does not currently delay scale-down. SimpleCloud may stop an unused server as soon as the group has enough spare capacity.
### Scale by available servers
Choose **Servers** when you want a set number of servers ready for players. **Player Threshold** decides when a server is too full to count as ready.
For example, with **Minimum Servers** set to `2` and **Player Threshold** set to `0.75`, SimpleCloud keeps two servers below 75% capacity ready when possible. It starts more servers as those servers fill, up to **Maximum Servers**.
**Servers** mode only starts servers. It does not stop extra servers automatically. Choose **Slots** if the group should also scale down.
Save your changes, then watch the **Servers** tab to confirm the group moves toward the new capacity.
## Choose where servers can run
Open **Settings > Deployment** to choose which serverhosts may run the group. Leave every serverhost enabled unless the group must run on specific machines.
When you enable only some serverhosts, drag them into the order SimpleCloud should prefer them. SimpleCloud can use another enabled serverhost when a preferred one has no capacity.
If you disable every serverhost, SimpleCloud cannot start a new server for the group.
## Apply group changes
Changes to software, plugins, or server files apply when new servers start. After saving a change, open the group's action menu and use **Hold to rolling restart** to apply it to running servers.
A rolling restart replaces the group's servers one at a time so capacity remains available during the change. **Restart all** stops the current servers together, and deactivating the group stops them without starting replacements.
Files stored only inside a group server are temporary. Use a persistent server for data that must survive replacement.
## Troubleshooting
Make sure the group is active, **Minimum Servers** is at least `1`, and at least one enabled serverhost is online with enough free memory.
Open the affected server's logs and the serverhost logs. They show whether software setup, a workflow, or the server process failed.
Check **Minimum Servers**, **Maximum Servers**, and the setting used by your mode: **Available Slots** for Slots mode or **Player Threshold** for Servers mode. Remember that only Slots mode automatically stops extra servers.