c12s-kubespray/docs/vagrant.md

# Vagrant

Assuming you have Vagrant 2.0+ installed with virtualbox, libvirt/qemu or
vmware, but is untested) you should be able to launch a 3 node Kubernetes
cluster by simply running `vagrant up`.

This will spin up 3 VMs and install kubernetes on them.
Once they are completed you can connect to any of them by running `vagrant ssh k8s-[1..3]`.

To give an estimate of the expected duration of a provisioning run:
On a dual core i5-6300u laptop with an SSD, provisioning takes around 13
to 15 minutes, once the container images and other files are cached.
Note that libvirt/qemu is recommended over virtualbox as it is quite a bit
faster, especially during boot-up time.

For proper performance a minimum of 12GB RAM is recommended.
It is possible to run a 3 node cluster on a laptop with 8GB of RAM using
the default Vagrantfile, provided you have 8GB zram swap configured and
not much more than a browser and a mail client running.
If you decide to run on such a machine, then also make sure that any tmpfs
devices, that are mounted, are mostly empty and disable any swapfiles
mounted on HDD/SSD or you will be in for some serious swap-madness.
Things can get a bit sluggish during provisioning, but when that's done,
the system will actually be able to perform quite well.

## Customize Vagrant

You can override the default settings in the `Vagrantfile` either by
directly modifying the `Vagrantfile` or through an override file.
In the same directory as the `Vagrantfile`, create a folder called
`vagrant` and create `config.rb` file in it.
An example of how to configure this file is given below.

## Use alternative OS for Vagrant

By default, Vagrant uses Ubuntu 18.04 box to provision a local cluster.
You may use an alternative supported operating system for your local cluster.

Customize `$os` variable in `Vagrantfile` or as override, e.g.,:

```ShellSession
echo '$os = "flatcar-stable"' >> vagrant/config.rb
```

The supported operating systems for vagrant are defined in the `SUPPORTED_OS`
constant in the `Vagrantfile`.

## File and image caching

Kubespray can take quite a while to start on a laptop. To improve provisioning
speed, the variable 'download_run_once' is set. This will make kubespray
download all files and containers just once and then redistributes them to
the other nodes and as a bonus, also cache all downloads locally and re-use
them on the next provisioning run. For more information on download settings
see [download documentation](/docs/downloads.md).

## Example use of Vagrant

The following is an example of setting up and running kubespray using `vagrant`.
For repeated runs, you could save the script to a file in the root of the
kubespray and run it by executing `source <name_of_the_file>`.

```ShellSession
# use virtualenv to install all python requirements
VENVDIR=venv
virtualenv --python=/usr/bin/python3.7 $VENVDIR
source $VENVDIR/bin/activate
pip install -r requirements.txt

# prepare an inventory to test with
INV=inventory/my_lab
rm -rf ${INV}.bak &> /dev/null
mv ${INV} ${INV}.bak &> /dev/null
cp -a inventory/sample ${INV}
rm -f ${INV}/hosts.ini

# customize the vagrant environment
mkdir vagrant
cat << EOF > vagrant/config.rb
\$instance_name_prefix = "kub"
\$vm_cpus = 1
\$num_instances = 3
\$os = "centos-bento"
\$subnet = "10.0.20"
\$network_plugin = "flannel"
\$inventory = "$INV"
\$shared_folders = { 'temp/docker_rpms' => "/var/cache/yum/x86_64/7/docker-ce/packages" }
EOF

# make the rpm cache
mkdir -p temp/docker_rpms

vagrant up

# make a copy of the downloaded docker rpm, to speed up the next provisioning run
scp kub-1:/var/cache/yum/x86_64/7/docker-ce/packages/* temp/docker_rpms/

# copy kubectl access configuration in place
mkdir $HOME/.kube/ &> /dev/null
ln -s $PWD/$INV/artifacts/admin.conf $HOME/.kube/config
# make the kubectl binary available
sudo ln -s $PWD/$INV/artifacts/kubectl /usr/local/bin/kubectl
#or
export PATH=$PATH:$PWD/$INV/artifacts
```

If a vagrant run failed and you've made some changes to fix the issue causing
the fail, here is how you would re-run ansible:

```ShellSession
ansible-playbook -vvv -i .vagrant/provisioners/ansible/inventory/vagrant_ansible_inventory cluster.yml
```

If all went well, you check if it's all working as expected:

```ShellSession
kubectl get nodes
```

The output should look like this:

```ShellSession
$ kubectl get nodes
NAME    STATUS   ROLES                  AGE     VERSION
kub-1   Ready    control-plane,master   4m37s   v1.22.5
kub-2   Ready    control-plane,master   4m7s    v1.22.5
kub-3   Ready    <none>                 3m7s    v1.22.5
```

Another nice test is the following:

```ShellSession
kubectl get pods --all-namespaces -o wide
```

Which should yield something like the following:

```ShellSession
$ kubectl get pods --all-namespaces -o wide
NAMESPACE            NAME                                      READY   STATUS    RESTARTS   AGE     IP            NODE    NOMINATED NODE   READINESS GATES
kube-system          coredns-8474476ff8-m2469                  1/1     Running   0          2m45s   10.233.65.2   kub-2   <none>           <none>
kube-system          coredns-8474476ff8-v5wzj                  1/1     Running   0          2m41s   10.233.64.3   kub-1   <none>           <none>
kube-system          dns-autoscaler-5ffdc7f89d-76tnv           1/1     Running   0          2m43s   10.233.64.2   kub-1   <none>           <none>
kube-system          kube-apiserver-kub-1                      1/1     Running   1          4m54s   10.0.20.101   kub-1   <none>           <none>
kube-system          kube-apiserver-kub-2                      1/1     Running   1          4m33s   10.0.20.102   kub-2   <none>           <none>
kube-system          kube-controller-manager-kub-1             1/1     Running   1          5m1s    10.0.20.101   kub-1   <none>           <none>
kube-system          kube-controller-manager-kub-2             1/1     Running   1          4m33s   10.0.20.102   kub-2   <none>           <none>
kube-system          kube-flannel-9xgf5                        1/1     Running   0          3m10s   10.0.20.102   kub-2   <none>           <none>
kube-system          kube-flannel-l8jbl                        1/1     Running   0          3m10s   10.0.20.101   kub-1   <none>           <none>
kube-system          kube-flannel-zss4t                        1/1     Running   0          3m10s   10.0.20.103   kub-3   <none>           <none>
kube-system          kube-multus-ds-amd64-bhpc9                1/1     Running   0          3m2s    10.0.20.103   kub-3   <none>           <none>
kube-system          kube-multus-ds-amd64-n6vl8                1/1     Running   0          3m2s    10.0.20.102   kub-2   <none>           <none>
kube-system          kube-multus-ds-amd64-qttgs                1/1     Running   0          3m2s    10.0.20.101   kub-1   <none>           <none>
kube-system          kube-proxy-2x4jl                          1/1     Running   0          3m33s   10.0.20.101   kub-1   <none>           <none>
kube-system          kube-proxy-d48r7                          1/1     Running   0          3m33s   10.0.20.103   kub-3   <none>           <none>
kube-system          kube-proxy-f45lp                          1/1     Running   0          3m33s   10.0.20.102   kub-2   <none>           <none>
kube-system          kube-scheduler-kub-1                      1/1     Running   1          4m54s   10.0.20.101   kub-1   <none>           <none>
kube-system          kube-scheduler-kub-2                      1/1     Running   1          4m33s   10.0.20.102   kub-2   <none>           <none>
kube-system          nginx-proxy-kub-3                         1/1     Running   0          3m33s   10.0.20.103   kub-3   <none>           <none>
kube-system          nodelocaldns-cg9tz                        1/1     Running   0          2m41s   10.0.20.102   kub-2   <none>           <none>
kube-system          nodelocaldns-htswt                        1/1     Running   0          2m41s   10.0.20.103   kub-3   <none>           <none>
kube-system          nodelocaldns-nsp7s                        1/1     Running   0          2m41s   10.0.20.101   kub-1   <none>           <none>
local-path-storage   local-path-provisioner-66df45bfdd-km4zg   1/1     Running   0          2m54s   10.233.66.2   kub-3   <none>           <none>
```