--- title: Multi-Node Test Environment weight: 12100 indent: true --- # Multi-Node Test Environment - [Using KVM/QEMU and Kubespray](#using-kvmqemu-and-kubespray) - [Using VirtualBox and k8s-vagrant-multi-node](#using-virtualbox-and-k8s-vagrant-multi-node) - [Using Vagrant and libvirt](#using-vagrant-on-linux-with-libvirt) ## Using KVM/QEMU and Kubespray ### Setup expectation There are a bunch of pre-requisites to be able to deploy the following environment. Such as: * A Linux workstation (CentOS or Fedora) * KVM/QEMU installation * docker service allowing insecure local repository For other Linux distribution, there is no guarantee the following will work. However adapting commands (apt/yum/dnf) could just work. ### Prerequisites installation On your host machine, execute `tests/scripts/multi-node/rpm-system-prerequisites.sh` (or do the equivalent for your distribution) Edit `/etc/docker/daemon.json` to add insecure-registries: ``` { "insecure-registries": ["172.17.8.1:5000"] } ``` ### Deploy Kubernetes with Kubespray Clone it: ```bash git clone https://github.com/kubernetes-incubator/kubespray cd kubespray ``` In order to successfully deploy Kubernetes with Kubespray, you must have this code: https://github.com/kubernetes-incubator/kubespray/pull/2153 and https://github.com/kubernetes-incubator/kubespray/pull/2271. Edit `inventory/group_vars/k8s-cluster.yml` with: ```bash docker_options: {% raw %}"--insecure-registry=172.17.8.1:5000 --insecure-registry={{ kube_service_addresses }} --graph={{ docker_daemon_graph }} {{ docker_log_opts }}"{% endraw %} ``` FYI: `172.17.8.1` is the libvirt bridge IP, so it's reachable from all your virtual machines. This means a registry running on the host machine is reachable from the virtual machines running the Kubernetes cluster. Create Vagrant's variable directory: ```bash mkdir vagrant/ ``` Put `tests/scripts/multi-node/config.rb` in `vagrant/`. You can adapt it at will. Feel free to adapt `num_instances`. Deploy! ```bash vagrant up --no-provision ; vagrant provision ``` Go grab a coffee: ``` PLAY RECAP ********************************************************************* k8s-01 : ok=351 changed=111 unreachable=0 failed=0 k8s-02 : ok=230 changed=65 unreachable=0 failed=0 k8s-03 : ok=230 changed=65 unreachable=0 failed=0 k8s-04 : ok=229 changed=65 unreachable=0 failed=0 k8s-05 : ok=229 changed=65 unreachable=0 failed=0 k8s-06 : ok=229 changed=65 unreachable=0 failed=0 k8s-07 : ok=229 changed=65 unreachable=0 failed=0 k8s-08 : ok=229 changed=65 unreachable=0 failed=0 k8s-09 : ok=229 changed=65 unreachable=0 failed=0 Friday 12 January 2018 10:25:45 +0100 (0:00:00.017) 0:17:24.413 ******** =============================================================================== download : container_download | Download containers if pull is required or told to always pull (all nodes) - 192.44s kubernetes/preinstall : Update package management cache (YUM) --------- 178.26s download : container_download | Download containers if pull is required or told to always pull (all nodes) - 102.24s docker : ensure docker packages are installed -------------------------- 57.20s download : container_download | Download containers if pull is required or told to always pull (all nodes) -- 52.33s kubernetes/preinstall : Install packages requirements ------------------ 25.18s download : container_download | Download containers if pull is required or told to always pull (all nodes) -- 23.74s download : container_download | Download containers if pull is required or told to always pull (all nodes) -- 18.90s download : container_download | Download containers if pull is required or told to always pull (all nodes) -- 15.39s kubernetes/master : Master | wait for the apiserver to be running ------ 12.44s download : container_download | Download containers if pull is required or told to always pull (all nodes) -- 11.83s download : container_download | Download containers if pull is required or told to always pull (all nodes) -- 11.66s kubernetes/node : install | Copy kubelet from hyperkube container ------ 11.44s download : container_download | Download containers if pull is required or told to always pull (all nodes) -- 11.41s download : container_download | Download containers if pull is required or told to always pull (all nodes) -- 11.00s docker : Docker | pause while Docker restarts -------------------------- 10.22s kubernetes/secrets : Check certs | check if a cert already exists on node --- 6.05s kubernetes-apps/network_plugin/flannel : Flannel | Wait for flannel subnet.env file presence --- 5.33s kubernetes/master : Master | wait for kube-scheduler -------------------- 5.30s kubernetes/master : Copy kubectl from hyperkube container --------------- 4.77s [leseb@tarox kubespray]$ [leseb@tarox kubespray]$ [leseb@tarox kubespray]$ vagrant ssh k8s-01 Last login: Fri Jan 12 09:22:18 2018 from 192.168.121.1 [vagrant@k8s-01 ~]$ kubectl get nodes NAME STATUS ROLES AGE VERSION k8s-01 Ready master,node 2m v1.9.0+coreos.0 k8s-02 Ready node 2m v1.9.0+coreos.0 k8s-03 Ready node 2m v1.9.0+coreos.0 k8s-04 Ready node 2m v1.9.0+coreos.0 k8s-05 Ready node 2m v1.9.0+coreos.0 k8s-06 Ready node 2m v1.9.0+coreos.0 k8s-07 Ready node 2m v1.9.0+coreos.0 k8s-08 Ready node 2m v1.9.0+coreos.0 k8s-09 Ready node 2m v1.9.0+coreos.0 ``` ### Running the Kubernetes Dashboard UI kubespray sets up the Dashboard pod by default, but you must authenticate with a bearer token, even for localhost access with kubectl proxy. To allow access, one possible solution is to: 1) Create an admin user by creating admin-user.yaml with these contents (and using kubectl -f create admin-user.yaml): ```yaml apiVersion: v1 kind: ServiceAccount metadata: name: admin-user namespace: kube-system ``` 2) Grant that user the ClusterRole authorization by creating and applying admin-user-cluster.role.yaml: ```yaml apiVersion: rbac.authorization.k8s.io/v1 kind: ClusterRoleBinding metadata: name: admin-user roleRef: apiGroup: rbac.authorization.k8s.io kind: ClusterRole name: cluster-admin subjects: - kind: ServiceAccount name: admin-user namespace: kube-system ``` 3) Find the admin-user token in the kube-system namespace: ```bash kubectl -n kube-system describe secret $(kubectl -n kube-system get secret | grep admin-user | awk '{print $1}') ``` and you can use that token to log into the UI at http://localhost:8001/ui. (See [https://github.com/kubernetes/dashboard/wiki/Creating-sample-user](https://github.com/kubernetes/dashboard/wiki/Creating-sample-user)) ### Development workflow on the host Everything should happen on the host, your development environment will reside on the host machine NOT inside the virtual machines running the Kubernetes cluster. Now, please refer to [https://rook.io/docs/rook/master/development-flow.html](https://rook.io/docs/rook/master/development-flow.html) to setup your development environment (go, git etc). At this stage, Rook should be cloned on your host. From your Rook repository (should be $GOPATH/src/github.com/rook) location execute `bash tests/scripts/multi-node/build-rook.sh`. During its execution, `build-rook.sh` will purge all running Rook pods from the cluster, so that your latest container image can be deployed. Furthermore, **all Ceph data and config will be purged** as well. Ensure that you are done with all existing state on your test cluster before executing `build-rook.sh` as it will clear everything. Each time you build and deploy with `build-rook.sh`, the virtual machines (k8s-0X) will pull the new container image and run your new Rook code. You can run `bash tests/scripts/multi-node/build-rook.sh` as many times as you want to rebuild your new rook image and redeploy a cluster that is running your new code. From here, resume your dev, change your code and test it by running `bash tests/scripts/multi-node/build-rook.sh`. ### Teardown Typically, to flush your environment you will run the following from within kubespray's git repository. This action will be performed on the host: ```bash [user@host-machine kubespray]$ vagrant destroy -f ``` Also, if you were using `kubectl` on that host machine, you can resurrect your old configuration by renaming `$HOME/.kube/config.before.rook.$TIMESTAMP` with `$HOME/.kube/config`. If you were not using `kubectl`, feel free to simply remove `$HOME/.kube/config.rook`. ## Using VirtualBox and k8s-vagrant-multi-node ### Prerequisites Be sure to follow the prerequisites here: https://github.com/galexrt/k8s-vagrant-multi-node/tree/master#prerequisites. ### Quickstart To start up the environment just run `./tests/scripts/k8s-vagrant-multi-node.sh up`. This will bring up one master and 2 workers by default. To change the amount of workers to bring up and their resources, be sure to checkout the [galexrt/k8s-vagrant-multi-node project README Variables section](https://github.com/galexrt/k8s-vagrant-multi-node/tree/master#variables). Just set or export the variables as you need on the script, e.g., either `NODE_COUNT=5 ./tests/scripts/k8s-vagrant-multi-node.sh up`, or `export NODE_COUNT=5` and then `./tests/scripts/k8s-vagrant-multi-node.sh up`. For more information or if you are experiencing issues, please create an issue at [GitHub galexrt/k8s-vagrant-multi-node](https://github.com/galexrt/k8s-vagrant-multi-node). ## Using Vagrant on Linux with libvirt See https://github.com/noahdesu/kubensis.