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website/docs/getting-started-guides/juju.md

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---
---
[Juju](https://jujucharms.com/docs/stable/about-juju) makes it easy to deploy
Kubernetes by provisioning, installing and configuring all the systems in
the cluster. Once deployed the cluster can easily scale up with one command
to increase the cluster size.
* TOC
{:toc}
## Prerequisites
> Note: If you're running kube-up, on Ubuntu - all of the dependencies
> will be handled for you. You may safely skip to the section:
> [Launch Kubernetes Cluster](#launch-kubernetes-cluster)
### On Ubuntu
[Install the Juju client](https://jujucharms.com/get-started)
> This documentation focuses on the juju 2.0 release which will be
> promoted to stable during its release cycle in April
To paraphrase, on your local Ubuntu system:
```shell
sudo add-apt-repository ppa:juju/devel
sudo apt-get update
sudo apt-get install juju2
```
If you are using another distro/platform - please consult the
[getting started guide](https://jujucharms.com/get-started) to install the
Juju dependencies for your platform.
### With Docker
If you are not using Ubuntu or prefer the isolation of Docker, you may
run the following:
> While this is a common target, the charmbox flavors of images are
> unofficial, and should be treated as Experimental. If you encounter any issues
> turning up the Kubernetes cluster with charmbox, please file a bug on the
> respective issue tracker [here](https://github.com/juju-solutions/charmbox/issues)
```shell
mkdir ~/.juju2
sudo docker run -v ~/.juju2:/home/ubuntu/.local/share/juju -ti jujusolutions/charmbox:devel
```
### Configure Juju to point a cloud
At this point you have access to the Juju client. If you wish to use a cloud,
you need to configure the credentials for the Juju cloud provider.
Juju supports a wide variety of public clouds to set up the credentials for
your chosen cloud see the
[cloud setup page](https://jujucharms.com/docs/devel/getting-started#2.-choose-a-cloud).
After configuration is complete test your setup with a `juju bootstrap`
command:
`juju bootstrap $cloudname $cloudtype` you are ready to launch the
Kubernetes cluster.
## Launch Kubernetes cluster
You will need to export the `KUBERNETES_PROVIDER` environment variable before
bringing up the cluster.
```shell
export KUBERNETES_PROVIDER=juju
cluster/kube-up.sh
```
If this is your first time running the `kube-up.sh` script, it will attempt to
install the required dependencies to get started with Juju.
Next it will deploy the kubernetes application, 3 units of etcd, and network
the units with flannel based Software Defined Networking (SDN) so containers
on different hosts can communicate with each other.
## Exploring the cluster
The `juju status` command provides information about each unit in the cluster:
```shell
$ juju status
... (omitted for brevity)
[Units]
ID WORKLOAD-STATE AGENT-STATE VERSION MACHINE PORTS PUBLIC-ADDRESS MESSAGE
etcd/0 active idle 2.0-beta2 1 54.146.50.29 Etcd leader running
kubernetes/0 active idle 2.0-beta2 2 6443/tcp,8088/tcp 54.205.204.227 Kubernetes follower running
kubernetes/1 active idle 2.0-beta2 3 6443/tcp,8088/tcp 54.145.57.114 Kubernetes leader running
... (omitted for brevity)
```
## Run some containers!
The `kubectl` file, the TLS certificates along with the configuration are
all available on the Kubernetes leader unit. Fetch the kubectl package so you
can run commands on the new Kuberntetes cluster.
Use the `juju status` command to figure out which Kubernetes unit is the leader
and copy the file from the leader:
```shell
juju scp kubernetes/1:kubectl_package.tar.gz .
tar xvfz kubectl_package.tar.gz
kubectl --config config get pods
```
If you are not on a Linux amd64 host system, you will need to find or build a
kubectl binary package for your architecture.
Put the config file in the home directory so you don't have to specify it on
the command line each time. The default location is `${HOME}/.kube/config`.
No pods will be available before starting a container:
```shell
kubectl get pods
NAME READY STATUSRESTARTS AGE
kubectl get replicationcontrollers
CONTROLLER CONTAINER(S) IMAGE(S) SELECTOR REPLICAS
```
We'll follow the aws-coreos example. Create a pod manifest: `pod.json`
```json
{
"apiVersion": "v1",
"kind": "Pod",
"metadata": {
"name": "hello",
"labels": {
"name": "hello",
"environment": "testing"
}
},
"spec": {
"containers": [{
"name": "hello",
"image": "quay.io/kelseyhightower/hello",
"ports": [{
"containerPort": 80,
"hostPort": 80
}]
}]
}
}
```
Create the pod with kubectl:
```shell
kubectl create -f pod.json
```
Get info on the pod:
```shell
kubectl get pods
```
To test the hello app, we need to locate which node is hosting
the container. We can use `juju run` and `juju status` commands to find
our hello app.
Exit out of our ssh session and run:
```shell
juju run --unit kubernetes/0 "docker ps -n=1"
...
juju run --unit kubernetes/1 "docker ps -n=1"
CONTAINER IDIMAGE COMMAND CREATED STATUS PORTS NAMES
02beb61339d8quay.io/kelseyhightower/hello:latest /hello About an hour ago Up About an hourk8s_hello....
```
We see "kubernetes/1" has our container, we can open port 80:
```shell
juju run --unit kubernetes/1 "open-port 80"
juju expose kubernetes
sudo apt-get install curl
curl $(juju status --format=oneline kubernetes/1 | cut -d' ' -f3)
```
Finally delete the pod:
```shell
juju ssh kubernetes/0
kubectl delete pods hello
```
## Scale out cluster
We can add node units like so:
```shell
juju add-unit kubernetes
```
Or multiple units at one time:
```shell
juju add-unit -n3 kubernetes
```
## Tear down cluster
We recommend that you use the `kube-down.sh` command when you are done using
the cluster, as it properly brings down the cloud and removes some of the
build directories.
```shell
./kube-down.sh
```
If you want stop the servers you can destroy your current Juju environment
(using the `juju env` command):
```shell
juju destroy-environment --force `juju env`
```
## More Info
Juju works with charms and bundles to deploy solutions. The code that stands up
a Kubernetes cluster is done in the charm code. The charm is built from using
a layered approach to keep the code smaller and more focused on the operations
of Kubernetes.
The Kubernetes layer and bundles can be found in the `kubernetes`
project on github.com:
- [Bundle location](https://github.com/kubernetes/kubernetes/tree/master/cluster/juju/bundles)
- [Kubernetes charm layer location](https://github.com/kubernetes/kubernetes/tree/master/cluster/juju/layers/kubernetes)
- [More about Juju](https://jujucharms.com)
### Cloud compatibility
Juju runs natively against a variety of public cloud providers. Juju currently
works with [Amazon Web Service](https://jujucharms.com/docs/stable/config-aws),
[Windows Azure](https://jujucharms.com/docs/stable/config-azure),
[DigitalOcean](https://jujucharms.com/docs/stable/config-digitalocean),
[Google Compute Engine](https://jujucharms.com/docs/stable/config-gce),
[HP Public Cloud](https://jujucharms.com/docs/stable/config-hpcloud),
[Joyent](https://jujucharms.com/docs/stable/config-joyent),
[LXC](https://jujucharms.com/docs/stable/config-LXC), any
[OpenStack](https://jujucharms.com/docs/stable/config-openstack) deployment,
[Vagrant](https://jujucharms.com/docs/stable/config-vagrant), and
[Vmware vSphere](https://jujucharms.com/docs/stable/config-vmware).
If you do not see your favorite cloud provider listed many clouds with ssh
access can be configured for
[manual provisioning](https://jujucharms.com/docs/stable/config-manual).
The Juju Kubernetes work is curated by a very small group of community members.
Let us know how we are doing. If you find any problems please open an
[issue at the kubernetes project](https://github.com/kubernetes/kubernetes/issues)
and tag it with "juju" so we can find it.
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