Local Binary

Skill: Local Binary Setup

Objective

Download pre-built Danube binaries from GitHub releases and run brokers directly on the host machine. The simplest setup — no Docker, no build tools, just download and run.

Prerequisites

Run the prerequisites check before setup:

./scripts/check_prereqs.sh binary

This verifies curl, tar, port availability, and no conflicting Danube processes.

How to Run

Once prerequisites are confirmed, run the setup script:

# Standalone (single broker, no config needed)
./scripts/setup_local_binary.sh standalone v0.15.0

# 3-broker cluster
./scripts/setup_local_binary.sh cluster v0.15.0 3

# Cleanup
./scripts/cleanup.sh binary

The script is at scripts/setup_local_binary.sh — read it for the full implementation details.

Modes

Standalone

• Runs a single broker with --mode standalone
• No config file needed — the broker auto-generates sensible defaults
• Broker listens on 127.0.0.1:6650 (client) and 127.0.0.1:50051 (admin)
• Raft runs in single-node mode — cluster status, brokers balance, and brokers leader-broker are not available and will return errors
• Verification: danube-admin brokers list shows one broker as active

Cluster

• Runs N brokers (default 3) with --config-file and port offsets
• Config is copied from configs/default.yml into $TEST_RUN/danube_broker.yml
• Seed nodes are passed via --seed-nodes CLI flag (not embedded in the config)
• Raft elects a leader within ~10 seconds
• Verification: danube-admin brokers list shows all brokers active, cluster status shows a leader

Edge (manual — not in setup script)

Edge mode requires a running cluster first. It is not covered by the setup script because it depends on having a cluster already up.

1. Start a cluster (standalone or multi-broker) using the script
2. Create the edge namespace on the cluster: danube-admin namespaces create edge1

• The namespace name must match edge.edge_name in configs/edge.yaml
• Without this, the edge broker fails with "Unable to find the namespace"

1. Copy the edge config: cp configs/edge.yaml "$TEST_RUN/edge.yaml"

• cluster_url defaults to http://127.0.0.1:6650 — correct for local setup
• schema_subject in topic mappings is optional — remove it for basic testing, otherwise the referenced schemas must be pre-registered on the cluster

1. Start the edge broker from inside $TEST_RUN/:

``bash "$DANUBE_BIN/danube-broker" \ --mode edge \ --data-dir "./data/edge" \ --edge-config "./edge.yaml" \ --broker-addr "0.0.0.0:6653" \ --admin-addr "0.0.0.0:50054" \ --raft-addr "0.0.0.0:7653" \ > "./logs/edge_broker.log" 2>&1 & ``

1. Test MQTT ingestion (requires mosquitto_pub):

``bash mosquitto_pub -h 127.0.0.1 -p 1883 \ -t "device/sensor-1/telemetry" \ -m '{"temperature": 25.5, "device_id": "sensor-1"}' ``

Key Concepts

Binary Downloads Are Shared

Binaries live in bin// at the repo root and are reused across all test runs. The script skips download if they already exist.

Release URL pattern:

https://github.com/danube-messaging/danube/releases/download//--.

Three binaries are downloaded: danube-broker, danube-cli, danube-admin.

Brokers Run From Inside $TEST_RUN

The script cds into the test run directory before starting brokers. This ensures all relative paths in the config (e.g., local_wal_root: "./data/wal") resolve inside the test run — keeping all data isolated.

Config Path Behavior

• meta_store.data_dir — overridden by --data-dir CLI flag (Raft data)
• storage.local_wal_root — NOT overridden by any CLI flag. It reads from the config file and resolves relative to the broker's working directory. This is why brokers must run from $TEST_RUN/.

CLI Quirks

• danube-broker does not support --version or --help. Only danube-admin and danube-cli support --version.
• Readiness checks should use danube-admin brokers list — it works in all modes (standalone, cluster, edge).
• danube-admin cluster status, brokers leader-broker, and brokers balance only work in cluster mode.

Verification

The setup scripts (scripts/setup_local_binary.sh) run these checks automatically. The expected output is documented here so the AI can confirm the setup is healthy.

danube-admin brokers list

All brokers must show status active. In cluster mode, one broker has role Cluster_Leader, the rest are Cluster_Follower.

BROKER ID       STATUS   ADDRESS              ROLE              ADMIN ADDR
---------------------------------------------------------------------------
5804156356...   active   http://0.0.0.0:6650  Cluster_Leader    http://0.0.0.0:50051
9393761688...   active   http://0.0.0.0:6651  Cluster_Follower  http://0.0.0.0:50052
1293191161...   active   http://0.0.0.0:6652  Cluster_Follower  http://0.0.0.0:50053

In standalone mode, one broker appears with role None.

danube-admin cluster status (cluster mode only)

The Leader field must show a valid node ID (not none). All broker node IDs should appear in the Voters list.

Raft Cluster Status:
  Self Node ID:  5804156356532636512
  Raft Address:  0.0.0.0:7650
  Leader:        5804156356532636512
  Term:          1
  Last Applied:  18
  Voters:        [5804156356532636512, 9393761688591103413, 12931911617355319510]

Fail indicators:

• Any broker with status other than active
• Leader: none in cluster status (no leader elected)
• Fewer voters than expected brokers
• ERROR, PANIC, or FATAL in broker logs: grep -i "ERROR\|PANIC\|FATAL" "$TEST_RUN/logs/"*.log

Troubleshooting

• Binary not found or wrong architecture: The script auto-detects OS/arch. If it fails, check uname -s and uname -m and verify the release page has a matching archive.

• Permission denied: chmod +x bin//danube-*

• Port already in use: ss -lntp | grep . Kill the conflicting process or run ./scripts/cleanup.sh binary first.

• Raft cluster not forming: Check logs: tail -20 "$TEST_RUN/logs/broker_6650.log". Ensure seed_nodes are correct.

• Standalone mode ignores config file: By design. --mode standalone auto-generates config. To use a custom config, omit --mode standalone and use --config-file instead.

• Edge broker: "Unable to find the namespace": Create the namespace first: danube-admin namespaces create .

• Edge broker: stale Raft data: Delete the edge data dir before restarting: rm -rf $TEST_RUN/data/edge

• Edge broker: "schema not resolved": Remove schema_subject from topic mappings in the edge config, or pre-register the schemas on the cluster first.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: danube-messaging
• Source: danube-messaging/danube-agent-skills
• License: Apache-2.0

Install and usage instructions live in the source repository linked above.