Docker & deployment

The repo publishes a multi-arch (linux/amd64, linux/arm64) distroless image to GitHub Container Registry on every push to main:

ghcr.io/zachbroad/dns-monitor:latest
ghcr.io/zachbroad/dns-monitor:<version>   # semver tags
ghcr.io/zachbroad/dns-monitor:sha-<short> # commit pins

Minimal run

docker run --rm -p 8080:8080 ghcr.io/zachbroad/dns-monitor:latest

This uses the default config.yaml baked into the image. The SQLite database lives inside the container and is lost on exit.

With a custom config and persistent history

Create config.yaml on the host and mount it alongside a data volume:

interval: 30s
listen: ":8080"
db_path: "/data/dns-monitor.db"
targets:
  - name: example-a
    host: example.com
    type: A
    expect:
      - 93.184.216.34

docker run -d --name dns-monitor \
  -p 8080:8080 \
  -v "$PWD/config.yaml:/app/config.yaml:ro" \
  -v dns-monitor-data:/data \
  ghcr.io/zachbroad/dns-monitor:latest

Note the two volumes:

• config.yaml is mounted read-only at /app/config.yaml, overriding the bundled default.
• A named volume dns-monitor-data is mounted at /data, and db_path points inside it so history survives container restarts.

Docker Compose

services:
  dns-monitor:
    image: ghcr.io/zachbroad/dns-monitor:latest
    restart: unless-stopped
    ports:
      - "8080:8080"
    volumes:
      - ./config.yaml:/app/config.yaml:ro
      - dns-monitor-data:/data

volumes:
  dns-monitor-data:

Image details

• Base: gcr.io/distroless/static-debian12:nonroot — no shell, no package manager.
• User: nonroot (uid 65532).
• Binary: CGO disabled; modernc.org/sqlite is pure Go.
• Exposed port: 8080.
• Volume: /data.