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# Vagrant
Assuming you have Vagrant 2.0+ installed with virtualbox, libvirt/qemu orvmware, but is untested) you should be able to launch a 3 node Kubernetescluster 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 13to 15 minutes, once the container images and other files are cached.Note that libvirt/qemu is recommended over virtualbox as it is quite a bitfaster, 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 usingthe default Vagrantfile, provided you have 8GB zram swap configured andnot 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 tmpfsdevices, that are mounted, are mostly empty and disable any swapfilesmounted 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 bydirectly 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 `$os` variable in `Vagrantfile` or as override, e.g.,:
```ShellSessionecho '$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 provisioningspeed, the variable 'download_run_once' is set. This will make kubespraydownload all files and containers just once and then redistributes them tothe other nodes and as a bonus, also cache all downloads locally and re-usethem on the next provisioning run. For more information on download settingssee [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 thekubespray and run it by executing `source <name_of_the_file>`.
```ShellSession# use virtualenv to install all python requirements
VENVDIR=venvvirtualenv --python=/usr/bin/python3.7 $VENVDIRsource $VENVDIR/bin/activatepip install -r requirements.txt
# prepare an inventory to test with
INV=inventory/my_labrm -rf ${INV}.bak &> /dev/nullmv ${INV} ${INV}.bak &> /dev/nullcp -a inventory/sample ${INV}rm -f ${INV}/hosts.ini
# customize the vagrant environment
mkdir vagrantcat << EOF > vagrant/config.rb\$instance_name_prefix = "kub"\$vm_cpus = 1\$num_instances = 3\$os = "centos-bento"\$subnet = "10.0.20"\$network_plugin = "flannel"\$inventory = "$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/nullln -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/$INV/artifacts```
If a vagrant run failed and you've made some changes to fix the issue causingthe fail, here is how you would re-run ansible:
```ShellSessionansible-playbook -vvv -i .vagrant/provisioners/ansible/inventory/vagrant_ansible_inventory cluster.yml```
If all went well, you check if it's all working as expected:
```ShellSessionkubectl get nodes```
The output should look like this:
```ShellSession$ kubectl get nodesNAME STATUS ROLES AGE VERSIONkub-1 Ready control-plane,master 4m37s v1.22.5kub-2 Ready control-plane,master 4m7s v1.22.5kub-3 Ready <none> 3m7s v1.22.5```
Another nice test is the following:
```ShellSessionkubectl get pods --all-namespaces -o wide```
Which should yield something like the following:
```ShellSession$ kubectl get pods --all-namespaces -o wideNAMESPACE NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESkube-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>```
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