# maglevd

Health checker and gRPC control plane for VPP Maglev load balancing.

## Build

```sh
make          # builds bin/maglevd
make test     # runs all tests
make proto    # regenerates gRPC stubs from proto/maglev.proto
```

Requires Go 1.25+ and (for `make proto`) `protoc` with `protoc-gen-go` and `protoc-gen-go-grpc`.

## Run

```sh
maglevd --config /etc/maglev/maglev.yaml --grpc-addr :9090
```

| Flag | Env | Default |
|---|---|---|
| `--config` | `MAGLEV_CONFIG` | `/etc/maglev/frontend.yaml` |
| `--grpc-addr` | `MAGLEV_GRPC_ADDR` | `:9090` |
| `--log-level` | `MAGLEV_LOG_LEVEL` | `info` |

Send `SIGHUP` to reload the config without restarting. Backends whose health-check config is
unchanged continue probing uninterrupted.

`maglevd` requires `CAP_NET_RAW` to open raw ICMP sockets.

## Minimal config

```yaml
maglev:
  healthchecks:
    http:
      type: http
      port: 80
      params:
        path: /healthz
      interval: 2s
      timeout: 3s

  backends:
    web0: {address: 192.0.2.10, healthcheck: http}
    web1: {address: 192.0.2.11, healthcheck: http}

  frontends:
    web:
      address: 192.0.2.1
      protocol: tcp
      port: 80
      backends: [web0, web1]
```

See [docs/config-guide.md](docs/config-guide.md) for the full configuration reference.

## Docker

```sh
docker build -t maglevd .
docker run --cap-add NET_RAW -v /etc/maglev:/etc/maglev maglevd
```