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Introduction============
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, especcially during boot-up time.
For proper performance a mimimum 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 tnpfs 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 `$os` variable in `Vagrantfile` or as override, e.g.,:
echo '$os = "coreos-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 quit 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>.
```# 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 $INV/artifacts/admin.conf $HOME/.kube/config# make the kubectl binary available
sudo ln -s $INV/artifacts/kubectl /usr/local/bin/kubectl#or
export PATH=$PATH:$INV/artifacts```If a vagrant run failed and you've made some changes to fix the issue causing the fail, here is how you would re-run ansible:```ansible-playbook -vvv -i .vagrant/provisioners/ansible/inventory/vagrant_ansible_inventory cluster.yml```If all went well, you check if it's all working as expected:```kubectl get nodes```The output should look like this:```$ kubectl get nodesNAME STATUS ROLES AGE VERSIONkub-1 Ready master 32m v1.14.1kub-2 Ready master 31m v1.14.1kub-3 Ready <none> 31m v1.14.1```Another nice test is the following:```kubectl get po --all-namespaces -o wide```Which should yield something like the following:```NAMESPACE NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESkube-system coredns-97c4b444f-9wm86 1/1 Running 0 31m 10.233.66.2 kub-3 <none> <none>kube-system coredns-97c4b444f-g7hqx 0/1 Pending 0 30m <none> <none> <none> <none>kube-system dns-autoscaler-5fc5fdbf6-5c48k 1/1 Running 0 31m 10.233.66.3 kub-3 <none> <none>kube-system kube-apiserver-kub-1 1/1 Running 0 32m 10.0.20.101 kub-1 <none> <none>kube-system kube-apiserver-kub-2 1/1 Running 0 32m 10.0.20.102 kub-2 <none> <none>kube-system kube-controller-manager-kub-1 1/1 Running 0 32m 10.0.20.101 kub-1 <none> <none>kube-system kube-controller-manager-kub-2 1/1 Running 0 32m 10.0.20.102 kub-2 <none> <none>kube-system kube-flannel-8tgcn 2/2 Running 0 31m 10.0.20.103 kub-3 <none> <none>kube-system kube-flannel-b2hgt 2/2 Running 0 31m 10.0.20.101 kub-1 <none> <none>kube-system kube-flannel-zx4bc 2/2 Running 0 31m 10.0.20.102 kub-2 <none> <none>kube-system kube-proxy-4bjdn 1/1 Running 0 31m 10.0.20.102 kub-2 <none> <none>kube-system kube-proxy-l5tt5 1/1 Running 0 31m 10.0.20.103 kub-3 <none> <none>kube-system kube-proxy-x59q8 1/1 Running 0 31m 10.0.20.101 kub-1 <none> <none>kube-system kube-scheduler-kub-1 1/1 Running 0 32m 10.0.20.101 kub-1 <none> <none>kube-system kube-scheduler-kub-2 1/1 Running 0 32m 10.0.20.102 kub-2 <none> <none>kube-system kubernetes-dashboard-6c7466966c-jqz42 1/1 Running 0 31m 10.233.66.4 kub-3 <none> <none>kube-system nginx-proxy-kub-3 1/1 Running 0 32m 10.0.20.103 kub-3 <none> <none>kube-system nodelocaldns-2x7vh 1/1 Running 0 31m 10.0.20.102 kub-2 <none> <none>kube-system nodelocaldns-fpvnz 1/1 Running 0 31m 10.0.20.103 kub-3 <none> <none>kube-system nodelocaldns-h2f42 1/1 Running 0 31m 10.0.20.101 kub-1 <none> <none>```Create clusteradmin rbac and get the login token for the dashboard:```kubectl create -f contrib/misc/clusteradmin-rbac.ymlkubectl -n kube-system describe secret kubernetes-dashboard-token | grep 'token:' | grep -o '[^ ]\+$'```Copy it to the clipboard and now log in to the [dashboard](https://10.0.20.101:6443/api/v1/namespaces/kube-system/services/https:kubernetes-dashboard:/proxy/#!/login).
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