# Run etcd clusters inside containers

The following guide shows how to run etcd with rkt and Docker using the [static bootstrap process](clustering.md#static).

## Docker

In order to expose the etcd API to clients outside of Docker host, use the host IP address of the container. Please see [`docker inspect`](https://docs.docker.com/engine/reference/commandline/inspect) for more detail on how to get the IP address. Alternatively, specify `--net=host` flag to `docker run` command to skip placing the container inside of a separate network stack.

```
# For each machine
ETCD_VERSION=v3.0.0-beta.0
TOKEN=my-etcd-token
CLUSTER_STATE=new
NAME_1=etcd-node-0
NAME_2=etcd-node-1
NAME_3=etcd-node-2
HOST_1=10.20.30.1
HOST_2=10.20.30.2
HOST_3=10.20.30.3
CLUSTER=${NAME_1}=http://${HOST_1}:2380,${NAME_2}=http://${HOST_2}:2380,${NAME_3}=http://${HOST_3}:2380

# For node 1
THIS_NAME=${NAME_1}
THIS_IP=${HOST_1}
sudo docker run --net=host --name etcd quay.io/coreos/etcd:${ETCD_VERSION} \
    --data-dir=data.etcd --name ${THIS_NAME} \
	--initial-advertise-peer-urls http://${THIS_IP}:2380 --listen-peer-urls http://${THIS_IP}:2380 \
	--advertise-client-urls http://${THIS_IP}:2379 --listen-client-urls http://${THIS_IP}:2379 \
	--initial-cluster ${CLUSTER} \
	--initial-cluster-state ${CLUSTER_STATE} --initial-cluster-token ${TOKEN}

# For node 2
THIS_NAME=${NAME_2}
THIS_IP=${HOST_2}
sudo docker run --net=host --name etcd quay.io/coreos/etcd:${ETCD_VERSION} \
    --data-dir=data.etcd --name ${THIS_NAME} \
	--initial-advertise-peer-urls http://${THIS_IP}:2380 --listen-peer-urls http://${THIS_IP}:2380 \
	--advertise-client-urls http://${THIS_IP}:2379 --listen-client-urls http://${THIS_IP}:2379 \
	--initial-cluster ${CLUSTER} \
	--initial-cluster-state ${CLUSTER_STATE} --initial-cluster-token ${TOKEN}

# For node 3
THIS_NAME=${NAME_3}
THIS_IP=${HOST_3}
sudo docker run --net=host --name etcd quay.io/coreos/etcd:${ETCD_VERSION} \
    --data-dir=data.etcd --name ${THIS_NAME} \
	--initial-advertise-peer-urls http://${THIS_IP}:2380 --listen-peer-urls http://${THIS_IP}:2380 \
	--advertise-client-urls http://${THIS_IP}:2379 --listen-client-urls http://${THIS_IP}:2379 \
	--initial-cluster ${CLUSTER} \
	--initial-cluster-state ${CLUSTER_STATE} --initial-cluster-token ${TOKEN}
```

TODO: current etcd docker container is shipped with etcdctl, but the `ETCDCTL_API` environment value is not set inside the container. So currently there's no way to use etcdctl for v3 directly from the container (e.g. `docker exec etcd /etcdctl put foo bar` won't work).