PLEASE NOTE: This document applies to the HEAD of the source tree
If you are using a released version of Kubernetes, you should
refer to the docs that go with that version.
The latest release of this document can be found
[here](http://releases.k8s.io/release-1.1/docs/getting-started-guides/docker-multinode/master.md).
Documentation for other releases can be found at
[releases.k8s.io](http://releases.k8s.io).
--
## Installing a Kubernetes Master Node via Docker
We'll begin by setting up the master node. For the purposes of illustration, we'll assume that the IP of this machine
is `${MASTER_IP}`. We'll need to run several versioned Kubernetes components, so we'll assume that the version we want
to run is `${K8S_VERSION}`, which should hold a value such as "1.0.7".
There are two main phases to installing the master:
* [Setting up `flanneld` and `etcd`](#setting-up-flanneld-and-etcd)
* [Starting the Kubernetes master components](#starting-the-kubernetes-master)
## Setting up flanneld and etcd
_Note_:
There is a [bug](https://github.com/docker/docker/issues/14106) in Docker 1.7.0 that prevents this from working correctly.
Please install Docker 1.6.2 or Docker 1.7.1 or Docker 1.8.3.
### Setup Docker-Bootstrap
We're going to use `flannel` to set up networking between Docker daemons. Flannel itself (and etcd on which it relies) will run inside of
Docker containers themselves. To achieve this, we need a separate "bootstrap" instance of the Docker daemon. This daemon will be started with
`--iptables=false` so that it can only run containers with `--net=host`. That's sufficient to bootstrap our system.
Run:
```sh
sudo sh -c 'docker -d -H unix:///var/run/docker-bootstrap.sock -p /var/run/docker-bootstrap.pid --iptables=false --ip-masq=false --bridge=none --graph=/var/lib/docker-bootstrap 2> /var/log/docker-bootstrap.log 1> /dev/null &'
```
_Important Note_:
If you are running this on a long running system, rather than experimenting, you should run the bootstrap Docker instance under something like SysV init, upstart or systemd so that it is restarted
across reboots and failures.
### Startup etcd for flannel and the API server to use
Run:
```sh
sudo docker -H unix:///var/run/docker-bootstrap.sock run --net=host -d gcr.io/google_containers/etcd:2.2.1 /usr/local/bin/etcd --addr=127.0.0.1:4001 --bind-addr=0.0.0.0:4001 --data-dir=/var/etcd/data
```
Next, you need to set a CIDR range for flannel. This CIDR should be chosen to be non-overlapping with any existing network you are using:
```sh
sudo docker -H unix:///var/run/docker-bootstrap.sock run --net=host gcr.io/google_containers/etcd:2.2.1 etcdctl set /coreos.com/network/config '{ "Network": "10.1.0.0/16" }'
```
### Set up Flannel on the master node
Flannel is a network abstraction layer build by CoreOS, we will use it to provide simplified networking between our Pods of containers.
Flannel re-configures the bridge that Docker uses for networking. As a result we need to stop Docker, reconfigure its networking, and then restart Docker.
#### Bring down Docker
To re-configure Docker to use flannel, we need to take docker down, run flannel and then restart Docker.
Turning down Docker is system dependent, it may be:
```sh
sudo /etc/init.d/docker stop
```
or
```sh
sudo systemctl stop docker
```
or
```sh
sudo service docker stop
```
or it may be something else.
#### Run flannel
Now run flanneld itself:
```sh
sudo docker -H unix:///var/run/docker-bootstrap.sock run -d --net=host --privileged -v /dev/net:/dev/net quay.io/coreos/flannel:0.5.3
```
The previous command should have printed a really long hash, copy this hash.
Now get the subnet settings from flannel:
```sh
sudo docker -H unix:///var/run/docker-bootstrap.sock exec cat /run/flannel/subnet.env
```
#### Edit the docker configuration
You now need to edit the docker configuration to activate new flags. Again, this is system specific.
This may be in `/etc/default/docker` or `/etc/systemd/service/docker.service` or it may be elsewhere.
Regardless, you need to add the following to the docker command line:
```sh
--bip=${FLANNEL_SUBNET} --mtu=${FLANNEL_MTU}
```
#### Remove the existing Docker bridge
Docker creates a bridge named `docker0` by default. You need to remove this:
```sh
sudo /sbin/ifconfig docker0 down
sudo brctl delbr docker0
```
You may need to install the `bridge-utils` package for the `brctl` binary.
#### Restart Docker
Again this is system dependent, it may be:
```sh
sudo /etc/init.d/docker start
```
it may be:
```sh
systemctl start docker
```
## Starting the Kubernetes Master
Ok, now that your networking is set up, you can startup Kubernetes, this is the same as the single-node case, we will use the "main" instance of the Docker daemon for the Kubernetes components.
```sh
sudo docker run \
--volume=/:/rootfs:ro \
--volume=/sys:/sys:ro \
--volume=/dev:/dev \
--volume=/var/lib/docker/:/var/lib/docker:rw \
--volume=/var/lib/kubelet/:/var/lib/kubelet:rw \
--volume=/var/run:/var/run:rw \
--net=host \
--privileged=true \
--pid=host \
-d \
gcr.io/google_containers/hyperkube:v${K8S_VERSION} /hyperkube kubelet --api-servers=http://localhost:8080 --v=2 --address=0.0.0.0 --enable-server --hostname-override=127.0.0.1 --config=/etc/kubernetes/manifests-multi --cluster-dns=10.0.0.10 --cluster-domain=cluster.local
```
> Note that `--cluster-dns` and `--cluster-domain` is used to deploy dns, feel free to discard them if dns is not needed.
### Also run the service proxy
```sh
sudo docker run -d --net=host --privileged gcr.io/google_containers/hyperkube:v${K8S_VERSION} /hyperkube proxy --master=http://127.0.0.1:8080 --v=2
```
### Test it out
At this point, you should have a functioning 1-node cluster. Let's test it out!
Download the kubectl binary for `${K8S_VERSION}` (look at the URL in the following links) and make it available by editing your PATH environment variable.
([OS X](http://storage.googleapis.com/kubernetes-release/release/v1.0.7/bin/darwin/amd64/kubectl))
([linux](http://storage.googleapis.com/kubernetes-release/release/v1.0.7/bin/linux/amd64/kubectl))
For example, OS X:
```console
$ wget http://storage.googleapis.com/kubernetes-release/release/v${K8S_VERSION}/bin/darwin/amd64/kubectl
$ chmod 755 kubectl
$ PATH=$PATH:`pwd`
```
Linux:
```console
$ wget http://storage.googleapis.com/kubernetes-release/release/v${K8S_VERSION}/bin/linux/amd64/kubectl
$ chmod 755 kubectl
$ PATH=$PATH:`pwd`
```
Now you can list the nodes:
```sh
kubectl get nodes
```
This should print something like:
```console
NAME LABELS STATUS
127.0.0.1 kubernetes.io/hostname=127.0.0.1 Ready
```
If the status of the node is `NotReady` or `Unknown` please check that all of the containers you created are successfully running.
If all else fails, ask questions on [Slack](../../troubleshooting.md#slack).
### Next steps
Move on to [adding one or more workers](worker.md) or [deploy a dns](deployDNS.md)
[]()