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Modifications and improvements to the vagrant cluster README #1379

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Modifications and improvements to the vagrant cluster README #1379

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220 changes: 165 additions & 55 deletions docs/getting-started-guides/vagrant.md
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Original file line number Diff line number Diff line change
Expand Up @@ -8,13 +8,7 @@

### Setup

By default, the Vagrant setup will create a single kubernetes-master and 3 kubernetes-minions. You can control the number of minions that are instantiated via an environment variable on your host machine. If you plan to work with replicas, we strongly encourage you to work with enough minions to satisfy your largest intended replica size. If you do not plan to work with replicas, you can save some system resources by running with a single minion.

```
export KUBERNETES_NUM_MINIONS=3
```

To start your local cluster, open a terminal window and run:
By default, the Vagrant setup will create a single kubernetes-master and 3 kubernetes-minions. Each VM will take 512 MB, so make sure you have at least 2 GB of free memory. To start your local cluster, open a shell and run:

```
cd kubernetes
Expand Down Expand Up @@ -56,85 +50,191 @@ vagrant ssh minion-1
[vagrant@kubernetes-minion-1] $ sudo journalctl -r -u kubelet
```

### Interacting with your Kubernetes cluster with Vagrant.

With your Kubernetes cluster up, you can manage the nodes in your cluster with the regular Vagrant commands.

To push updates to new Kubernetes code after making source changes:
```
vagrant provision
```

To shutdown and then restart the cluster:
To stop and then restart the cluster:
```
vagrant halt
vagrant up
```

To destroy the cluster:
```
vagrant destroy -f
vagrant destroy
```

You can also use the cluster/kube-*.sh scripts to interact with vagrant based providers just like any other hosting platform for kubernetes.
Once your Vagrant machines are up and provisioned, the first thing to do is to check that you can use the `kubecfg.sh` script.
Set the `KUBERNETS_PROVIDER` environment variable and try to list the minions:

```
cd kubernetes
modify cluster/kube-env.sh:
KUBERNETES_PROVIDER="vagrant"
$ export KUBERNETES_PROVIDER=vagrant
$ ./cluster/kubecfg.sh list /minions
Minion identifier
----------
10.245.2.4
10.245.2.3
10.245.2.2
```

### Interacting with your Kubernetes cluster with the `kube-*` scripts.

Alternatively to using the vagrant commands, you can also use the `cluster/kube-*.sh` scripts to interact with the vagrant based provider just like any other hosting platform for kubernetes.

## build the binary required by kubecfg.sh
You need to build the binary required by `kube*` scripts:

```
hack/build-go.sh
```

Then bring up a vagrant cluster

cluster/kube-up.sh => brings up a vagrant cluster
cluster/kube-down.sh => destroys a vagrant cluster
cluster/kube-push.sh => updates a vagrant cluster
cluster/kubecfg.sh => interact with the cluster
```
cluster/kube-up.sh
```

Destroy the vagrant cluster

```
cluster/kube-down.sh
```

Update the vagrant cluster

```
cluster/kube-push.sh
```

Interact with the cluster

```
cluster/kubecfg.sh
```

### Authenticating with your master

To interact with the cluster, you must authenticate with the master when running cluster/kubecfg.sh commands.
When using the vagrant provider in Kubernetes, the `cluster/kubecfg.sh` script will cache your credentials in a `~/.kubernetes_auth_vagrant` file so you will not be prompted for them in the future.

If it's your first time using the cluster, your first invocation of cluster/kubecfg.sh will prompt you for credentials:
```
cat ~/.kubernetes_auth_vagrant
{ "User": "vagrant",
"Password": "vagrant"}
```

You should now be set to use the `cluster/kubecfg.sh` script. For example try to list the minions that you have started with:

```
cd kubernetes
cluster/kubecfg.sh list minions
Please enter Username: vagrant
Please enter Password: vagrant
```

### Running containers

Your cluster is running, you can list the minions in your cluster:

```
$ cluster/kubecfg.sh list /minions
Minion identifier
----------
10.245.2.4
10.245.2.3
10.245.2.2
```

The kubecfg.sh command will cache your credentials in a .kubernetes_auth file so you will not be prompted in the future.
Now start running some containers!

You can now use any of the cluster/kube-*.sh commands to interact with your VM machines.
Before starting a container there will be no pods, services and replication controllers.

```
cat ~/.kubernetes_auth
{"User":"vagrant","Password":"vagrant"}
$ cluster/kubecfg.sh list /pods
ID Image(s) Host Labels Status
---------- ---------- ---------- ---------- ----------

$ cluster/kubecfg.sh list /services
ID Labels Selector Port
---------- ---------- ---------- ----------

$ cluster/kubecfg.sh list /replicationControllers
ID Image(s) Selector Replicas
---------- ---------- ---------- ----------
```

If you try Kubernetes against multiple cloud providers, make sure this file is correct for your target environment.
Start a container running nginx with a replication controller and three replicas:

```
$cluster/kubecfg.sh -p 8080:80 run dockerfile/nginx 3 myNginx
```

### Running a container
When listing the pods, you will see that three containers have been started and are in Waiting state:

Your cluster is running, and you want to start running containers!
```
$ cluster/kubecfg.sh list /pods
ID Image(s) Host Labels Status
---------- ---------- ---------- ---------- ----------
781191ff-3ffe-11e4-9036-0800279696e1 dockerfile/nginx 10.245.2.4/10.245.2.4 replicationController=myNginx Waiting
7813c8bd-3ffe-11e4-9036-0800279696e1 dockerfile/nginx 10.245.2.2/10.245.2.2 replicationController=myNginx Waiting
78140853-3ffe-11e4-9036-0800279696e1 dockerfile/nginx 10.245.2.3/10.245.2.3 replicationController=myNginx Waiting
```

You can now use any of the cluster/kube-*.sh commands to interact with your VM machines.
You need to wait for the provisioning to complete, you can monitor the minions by doing

```
$ vagrant ssh minion-1
$ sudo docker images
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
<none> <none> 96864a7d2df3 26 hours ago 204.4 MB
google/cadvisor latest e0575e677c50 13 days ago 12.64 MB
kubernetes/pause latest 6c4579af347b 8 weeks ago 239.8 kB
```

Once the docker image for nginx has been downloaded, the container will start and you can list it:

```
$ sudo docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
dbe79bf6e25b dockerfile/nginx:latest "nginx" 21 seconds ago Up 19 seconds k8s--mynginx.8c5b8a3a--7813c8bd_-_3ffe_-_11e4_-_9036_-_0800279696e1.etcd--7813c8bd_-_3ffe_-_11e4_-_9036_-_0800279696e1--fcfa837f
fa0e29c94501 kubernetes/pause:latest "/pause" 8 minutes ago Up 8 minutes 0.0.0.0:8080->80/tcp k8s--net.a90e7ce4--7813c8bd_-_3ffe_-_11e4_-_9036_-_0800279696e1.etcd--7813c8bd_-_3ffe_-_11e4_-_9036_-_0800279696e1--baf5b21b
aa2ee3ed844a google/cadvisor:latest "/usr/bin/cadvisor - 38 minutes ago Up 38 minutes k8s--cadvisor.9e90d182--cadvisor_-_agent.file--4626b3a2
65a3a926f357 kubernetes/pause:latest "/pause" 39 minutes ago Up 39 minutes 0.0.0.0:4194->8080/tcp k8s--net.c5ba7f0e--cadvisor_-_agent.file--342fd561
```

Going back to listing the pods, services and replicationControllers, you now have:

```
$ cluster/kubecfg.sh list /pods
ID Image(s) Host Labels Status
---------- ---------- ---------- ---------- ----------
781191ff-3ffe-11e4-9036-0800279696e1 dockerfile/nginx 10.245.2.4/10.245.2.4 replicationController=myNginx Running
7813c8bd-3ffe-11e4-9036-0800279696e1 dockerfile/nginx 10.245.2.2/10.245.2.2 replicationController=myNginx Running
78140853-3ffe-11e4-9036-0800279696e1 dockerfile/nginx 10.245.2.3/10.245.2.3 replicationController=myNginx Running

$ cluster/kubecfg.sh list /services
ID Labels Selector Port
---------- ---------- ---------- ----------

$ cluster/kubecfg.sh list r/eplicationControllers
ID Image(s) Selector Replicas
---------- ---------- ---------- ----------
myNginx dockerfile/nginx replicationController=myNginx 3
```
cluster/kubecfg.sh list /pods
cluster/kubecfg.sh list /services
cluster/kubecfg.sh list /replicationControllers
cluster/kubecfg.sh -p 8080:80 run dockerfile/nginx 3 myNginx

## begin wait for provision to complete, you can monitor the minions by doing
vagrant ssh minion-1
sudo docker images
## you should see it pulling the dockerfile/nginx image, once the above command returns it
sudo docker ps
## you should see your container running!
exit
## end wait
We did not start any services, hence there is none listed. But we see three replicas displayed properly.
Check the [guestbook](examples/guestbook/README.md) application to learn how to create a service.
You can already play with resizing the replicas with:

## back on the host, introspect kubernetes!
cluster/kubecfg.sh list /pods
cluster/kubecfg.sh list /services
cluster/kubecfg.sh list /replicationControllers
```
$ cluster/kubecfg.sh resize myNginx 2
$ cluster/kubecfg.sh list /pods
ID Image(s) Host Labels Status
---------- ---------- ---------- ---------- ----------
7813c8bd-3ffe-11e4-9036-0800279696e1 dockerfile/nginx 10.245.2.2/10.245.2.2 replicationController=myNginx Running
78140853-3ffe-11e4-9036-0800279696e1 dockerfile/nginx 10.245.2.3/10.245.2.3 replicationController=myNginx Running
```

Congratulations!
Expand All @@ -147,29 +247,39 @@ The following will run all of the end-to-end testing scenarios assuming you set
hack/e2e-test.sh
```


### Troubleshooting

#### I just created the cluster, but I am getting authorization errors!

You probably have an incorrect ~/.kubernetes_auth file for the cluster you are attempting to contact.
You probably have an incorrect ~/.kubernetes_auth_vagrant file for the cluster you are attempting to contact.

```
rm ~/.kubernetes_auth
rm ~/.kubernetes_auth_vagrant
```

And when using kubecfg.sh, provide the correct credentials:
After using kubecfg.sh make sure that the correct credentials are set:

```
Please enter Username: vagrant
Please enter Password: vagrant
cat ~/.kubernetes_vagrant_auth
{
"User": "vagrant",
"Password": "vagrant"
}
```

#### I just created the cluster, but I do not see my container running!
#### I just created the cluster, but I do not see my container running !

If this is your first time creating the cluster, the kubelet on each minion schedules a number of docker pull requests to fetch prerequisite images. This can take some time and as a result may delay your initial pod getting provisioned.

#### I changed Kubernetes code, but it's not running!
#### I changed Kubernetes code, but it's not running !

Are you sure there was no build error? After running $ vagrant provision, scroll up and ensure that each Salt state was completed successfully on each box in the cluster.
Are you sure there was no build error? After running `$ vagrant provision`, scroll up and ensure that each Salt state was completed successfully on each box in the cluster.
It's very likely you see a build error due to an error in your source files!

#### I want to change the number of minions !

You can control the number of minions that are instantiated via the environment variable `KUBERNETES_NUM_MINIONS` on your host machine. If you plan to work with replicas, we strongly encourage you to work with enough minions to satisfy your largest intended replica size. If you do not plan to work with replicas, you can save some system resources by running with a single minion. You do this, by setting `KUBERNETES_NUM_MINIONS` to 1 like so:

```
export KUBERNETES_NUM_MINIONS=1
```