skywalking-java/docs/en/setup/backend/advanced-deployment.md

Advanced deployment

OAP servers inter communicate with each other in a cluster environment. In the cluster mode, you could run in different roles.

• Mixed(default)
• Receiver
• Aggregator

In some time, users want to deploy cluster nodes with explicit role. Then could use this.

Mixed

Default role, the OAP should take responsibilities of

1. Receive agent traces or metrics.
2. Do L1 aggregation
3. Internal communication(send/receive)
4. Do L2 aggregation
5. Persistence
6. Alarm

Receiver

The OAP should take responsibilities of

1. Receive agent traces or metrics.
2. Do L1 aggregation
3. Internal communication(send)

Aggregator

The OAP should take responsibilities of

1. Internal communication(receive)
2. Do L2 aggregation
3. Persistence
4. Alarm

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These roles are designed for complex deployment requirements based on security and network policy.

Kubernetes

If you are using our native Kubernetes coordinator, the labelSelector setting is used for Aggregator choose rules. Choose the right OAP deployment based on your requirements.