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226 lines
6.2 KiB
Markdown
226 lines
6.2 KiB
Markdown
## Getting started with Juju
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Juju handles provisioning machines and deploying complex systems to a
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wide number of clouds, supporting service orchestration once the bundle of
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services has been deployed.
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### Prerequisites
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> Note: If you're running kube-up, on ubuntu - all of the dependencies
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> will be handled for you. You may safely skip to the section:
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> [Launch Kubernetes Cluster](#launch-kubernetes-cluster)
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#### On Ubuntu
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[Install the Juju client](https://juju.ubuntu.com/install) on your
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local ubuntu system:
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sudo add-apt-repository ppa:juju/stable
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sudo apt-get update
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sudo apt-get install juju-core juju-quickstart
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#### With Docker
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If you are not using ubuntu or prefer the isolation of docker, you may
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run the following:
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mkdir ~/.juju
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sudo docker run -v ~/.juju:/home/ubuntu/.juju -ti whitmo/jujubox:latest
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At this point from either path you will have access to the `juju
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quickstart` command.
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To set up the credentials for your chosen cloud run:
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juju quickstart --constraints="mem=3.75G" -i
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Follow the dialogue and choose `save` and `use`. Quickstart will now
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bootstrap the juju root node and setup the juju web based user
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interface.
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## Launch Kubernetes cluster
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You will need to have the Kubernetes tools compiled before launching the cluster
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make all WHAT=cmd/kubectl
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export KUBERNETES_PROVIDER=juju
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cluster/kube-up.sh
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If this is your first time running the `kube-up.sh` script, it will install
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the required predependencies to get started with Juju, additionally it will
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launch a curses based configuration utility allowing you to select your cloud
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provider and enter the proper access credentials.
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Next it will deploy the kubernetes master, etcd, 2 minions with flannel based
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Software Defined Networking.
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## Exploring the cluster
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Juju status provides information about each unit in the cluster:
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juju status --format=oneline
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- docker/0: 52.4.92.78 (started)
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- flannel-docker/0: 52.4.92.78 (started)
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- kubernetes/0: 52.4.92.78 (started)
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- docker/1: 52.6.104.142 (started)
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- flannel-docker/1: 52.6.104.142 (started)
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- kubernetes/1: 52.6.104.142 (started)
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- etcd/0: 52.5.216.210 (started) 4001/tcp
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- juju-gui/0: 52.5.205.174 (started) 80/tcp, 443/tcp
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- kubernetes-master/0: 52.6.19.238 (started) 8080/tcp
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You can use `juju ssh` to access any of the units:
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juju ssh kubernetes-master/0
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## Run some containers!
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`kubectl` is available on the kubernetes master node. We'll ssh in to
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launch some containers, but one could use kubectl locally setting
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KUBERNETES_MASTER to point at the ip of `kubernetes-master/0`.
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No pods will be available before starting a container:
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kubectl get pods
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POD CONTAINER(S) IMAGE(S) HOST LABELS STATUS
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kubectl get replicationcontrollers
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CONTROLLER CONTAINER(S) IMAGE(S) SELECTOR REPLICAS
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We'll follow the aws-coreos example. Create a pod manifest: `pod.json`
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```
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{
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"apiVersion": "v1",
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"kind": "Pod",
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"metadata": {
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"name": "hello",
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"labels": {
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"name": "hello",
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"environment": "testing"
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}
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},
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"spec": {
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"containers": [{
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"name": "hello",
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"image": "quay.io/kelseyhightower/hello",
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"ports": [{
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"containerPort": 80,
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"hostPort": 80
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}]
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}]
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}
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}
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```
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Create the pod with kubectl:
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kubectl create -f pod.json
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Get info on the pod:
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kubectl get pods
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To test the hello app, we'll need to locate which minion is hosting
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the container. Better tooling for using juju to introspect container
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is in the works but for let'suse `juju run` and `juju status` to find
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our hello app.
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Exit out of our ssh session and run:
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juju run --unit kubernetes/0 "docker ps -n=1"
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...
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juju run --unit kubernetes/1 "docker ps -n=1"
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CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
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02beb61339d8 quay.io/kelseyhightower/hello:latest /hello About an hour ago Up About an hour k8s_hello....
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We see `kubernetes/1` has our container, we can open port 80:
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juju run --unit kubernetes/1 "open-port 80"
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juju expose kubernetes
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sudo apt-get install curl
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curl $(juju status --format=oneline kubernetes/1 | cut -d' ' -f3)
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Finally delete the pod:
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juju ssh kubernetes-master/0
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kubectl delete pods hello
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## Scale out cluster
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We can add minion units like so:
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juju add-unit docker # creates unit docker/2, kubernetes/2, docker-flannel/2
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## Launch the "petstore" example app
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The petstore example is available as a
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[juju action](https://jujucharms.com/docs/devel/actions).
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juju action do kubernetes-master/0
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Note: this example includes curl statements to exercise the app.
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## Tear down cluster
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./kube-down.sh
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or
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juju destroy-environment --force `juju env`
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## More Info
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Kubernetes Bundle on Github
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- [Bundle Repository](https://github.com/whitmo/bundle-kubernetes)
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* [Kubernetes master charm](https://github.com/whitmo/charm-kubernetes-master)
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* [Kubernetes mininion charm](https://github.com/whitmo/charm-kubernetes)
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- [Bundle Documentation](http://whitmo.github.io/bundle-kubernetes)
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- [More about Juju](https://juju.ubuntu.com)
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### Cloud compatibility
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Juju runs natively against a variety of cloud providers and can be
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made to work against many more using a generic manual provider.
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Provider | v0.15.0
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-------------- | -------
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AWS | TBD
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HPCloud | TBD
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OpenStack | TBD
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Joyent | TBD
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Azure | TBD
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Digital Ocean | TBD
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MAAS (bare metal) | TBD
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GCE | TBD
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Provider | v0.8.1
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-------------- | -------
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AWS | [Pass](http://reports.vapour.ws/charm-test-details/charm-bundle-test-parent-136)
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HPCloud | [Pass](http://reports.vapour.ws/charm-test-details/charm-bundle-test-parent-136)
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OpenStack | [Pass](http://reports.vapour.ws/charm-test-details/charm-bundle-test-parent-136)
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Joyent | [Pass](http://reports.vapour.ws/charm-test-details/charm-bundle-test-parent-136)
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Azure | TBD
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Digital Ocean | TBD
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MAAS (bare metal) | TBD
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GCE | TBD
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[]()
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