kubespray/docs/developers/vagrant.md

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# Vagrant
Assuming you have Vagrant 2.0+ installed with virtualbox or libvirt/qemu
(vmware may work, 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.
Example:
```ruby
# vagrant/config.rb
$instance_name_prefix = "kub"
$vm_cpus = 1
$num_instances = 3
$os = "centos8-bento"
$subnet = "10.0.20"
$network_plugin = "flannel"
$extra_vars = {
dns_domain: my.custom.domain
}
# or
$extra_vars = "path/to/extra/vars/file.yml"
```
For all available options look at the Vagrantfile (search for "CONFIG")
## Use alternative OS for Vagrant
By default, Vagrant uses Ubuntu 18.04 box to provision a local cluster.
You may use an alternative supported operating system for your local cluster.
Customize `$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/advanced/downloads.md).
## Example use of Vagrant
The following is an example of setting up and running kubespray using `vagrant`.
Customize your settings as shown, above, then run the commands:
```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
$ vagrant up
# Access the cluster
$ export INV=.vagrant/provisionners/ansible/inventory
$ export KUBECONFIG=${INV}/artifacts/admin.conf
# make the kubectl binary available
$ 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
vagrant provision
```
If all went well, you check if it's all working as expected:
```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
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>
```