Security Overview

Danube provides a layered security model that protects data in transit and controls access to cluster resources. Each layer can be enabled independently, but for production all three should be active.

Security Modes

The auth.mode setting in the broker configuration controls the overall security posture:

Mode	Encryption	Authentication	Authorization	Use Case
none	Off	Off	Off	Local development and testing
tls	TLS everywhere	JWT tokens	RBAC (default-deny)	Production deployments

When mode: none, all connections are unencrypted with no authentication. Any client can produce, consume, and manage the cluster without credentials.

Caution

Never use mode: none in production. All data flows in plaintext and any client has full access.

When mode: tls, the broker enables the full security stack:

• All client and inter-broker connections are encrypted with TLS
• Clients must present a valid JWT token to authenticate
• Every operation is checked against RBAC policies — if no policy grants access, the request is denied

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Security Layers

TLS & Certificates

Encrypt all network traffic. Server TLS for clients, mutual TLS for inter-broker communication.

Configure TLS →

Authentication (JWT)

Verify caller identity with signed JWT tokens. Offline token creation, no runtime key exchange.

Set up JWT →

Authorization (RBAC)

Control what each identity can do. Roles, bindings, scoped permissions with default-deny.

Configure RBAC →

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Quick Configuration

danube_broker.yml

auth:
  mode: tls

  tls:
    cert_file: "./cert/server-cert.pem"
    key_file: "./cert/server-key.pem"
    ca_file: "./cert/ca-cert.pem"

  jwt:
    secret_key: "your-secret-key"
    issuer: "danube-auth"
    expiration_time: 3600

  super_admins:
    - "admin"

admin_tls: false    # Enable TLS on admin API (recommended for remote access)

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Enforcement Summary

Authorization is enforced on every gRPC call across all broker services.

Data Plane

Operation	Required Permission	Resource
Topic lookup	Lookup	Topic
Topic partitions	Lookup	Topic
Create producer	Produce	Topic
Send message	Produce	Topic
Subscribe	Consume	Topic
Receive messages	Consume	Cluster
Acknowledge	Consume	Cluster

Admin Plane

Operation	Required Permission	Resource
Create/delete namespace	ManageNamespace	Namespace or Cluster
Create/delete topic	ManageTopic	Topic or Namespace
List/inspect brokers	ManageBroker	Cluster
Raft membership changes	ManageCluster	Cluster
Schema operations	ManageSchema	Schema Subject or Topic
Role/binding management	ManageCluster	Cluster