Server groups
Path: /admin-settings → Server Groups tab
Server groups define pools of voice processing servers. They control how calls are distributed across servers (load balancing) and how the platform automatically adds or removes instances based on demand (auto-scaling).
Server group
| Field | Required | Description |
|---|---|---|
| Group Name | Yes | Unique (e.g. premium, standard, us-east). |
| Description | No | Notes. |
| Servers Count | Auto | Current instances. |
| Enabled | Yes | Master toggle. |
Load balancing
| Field | Required | Default | Description |
|---|---|---|---|
| LB Method | Yes | — | round_robin / least_connections / weighted_round_robin. |
| Max Concurrent Calls | Yes | 100 | Per-server cap. When reached, new calls route elsewhere. |
| Priority | Yes | — | 1 – 10 (higher = preferred). Used when multiple groups are available. |
Auto-scaling
| Field | Required | Default | Description |
|---|---|---|---|
| Scaling Enabled | Yes | false | Master toggle. |
| Min Instances | Yes | 1 | Never scales below. |
| Max Instances | Yes | 10 | Never scales above. |
| Scale Up Threshold | Yes | 0.7 | Utilisation (0 – 1) triggering scale-up. |
| Scale Down Threshold | Yes | 0.3 | Utilisation triggering scale-down. |
| Cooldown Seconds | Yes | 300 | Min wait between scaling actions. |
| Scaling Provider | Yes | — | hetzner, aws, custom. |
| Scaling Config | No | — | Provider-specific JSON (machine type, region, SSH keys, …). |
How scaling works
- The Scaler monitors average utilisation per group.
- When utilisation > Scale Up Threshold, a new instance is provisioned.
- When utilisation < Scale Down Threshold, an instance is removed.
- The Cooldown prevents rapid up / down churn.
- Instance count stays between Min and Max.
Chain to teams
Server Group → Base Number → Team → Endpoint. Assign groups to base numbers (Base numbers) and to teams (Users and teams).
Workflows
Create a server group
Click Create → name + description → configure LB (method, max concurrent, priority) → configure auto-scaling if needed (enable, thresholds, min/max, cooldown, provider, config) → enable → save → assign in Base numbers and Teams.
Adjust scaling thresholds
Edit the group → adjust Scale Up / Down Threshold and Cooldown → save.
See also
- Base numbers.
- API server config — same auto-scaling model, applied to the API server.
- Voice operations.