ansible-kubernetes-vagrant

A local Kubernetes deployment using Vagrant and Ansible playbooks. This is based on the Ansible for DevOps book by Jeff Geerling. I made several modification in order to make it easier to use as an up to date lab environment for Kubernetes trainings.

The goal is to create 3 Kubernetes ready Debian VMs (1 master and 2 nodes), in order to be able to run Kubernetes tests or labs locally. The version of Kubernetes deployed is: 1.20.5-00.

After the Vagrant provisioning and ansible provisioning finish, we will have 3 VMs (IPs by default):

• master.k8s.test, ip: 192.168.84.2
• node1.k8s.test, ip: 192.168.84.3
• node2.k8s.test, ip: 192.168.84.4

We can then ssh to any VM with the credentials root/root or using the ssh-master.sh script (requires sshpass to be already installed).

ansible-kubernetes-vagrant$ ssh [email protected]
OR
ansible-kubernetes-vagrant$ ./ssh-master.sh


root@master:~# kubectl get nodes
NAME     STATUS   ROLES    AGE   VERSION
master   Ready    master   89m   v1.13.8
node1    Ready    <none>   88m   v1.13.8
node2    Ready    <none>   88m   v1.13.8

root@master:~# kubectl get pods --all-namespaces
NAMESPACE     NAME                             READY   STATUS    RESTARTS   AGE
kube-system   coredns-54ff9cd656-2hsh4         1/1     Running   0          89m
kube-system   coredns-54ff9cd656-rh78k         1/1     Running   0          89m
kube-system   etcd-master                      1/1     Running   0          88m
kube-system   kube-apiserver-master            1/1     Running   0          88m
kube-system   kube-controller-manager-master   1/1     Running   0          88m
kube-system   kube-flannel-ds-amd64-8x9sc      1/1     Running   0          89m
kube-system   kube-flannel-ds-amd64-cs6dl      1/1     Running   0          89m
kube-system   kube-flannel-ds-amd64-hp8hp      1/1     Running   0          88m
kube-system   kube-proxy-hvvvw                 1/1     Running   0          88m
kube-system   kube-proxy-mg854                 1/1     Running   0          89m
kube-system   kube-proxy-q9kwk                 1/1     Running   0          89m
kube-system   kube-scheduler-master            1/1     Running   0          88m

Different example of Kubernetes files are available in the /root/files directory:

root@master:~/files# ls
nginx-deployment.yaml  nginx-manual-scheduling.yaml  nginx-service.yaml

This folder is synced with the host machine to the guest machines allowing you to continue working on the project's files on the host machine (using an IDE for example), and the changes will be reflected on the VMs filesystem.

Installation:

Prerequisite:

• Ansible
• Ansible galaxy
• Vagrant
• VirtualBox

Commands:

1. Install the required roles

ansible-galaxy install -r requirements.yml 

2. Create the VMs

vagrant up

3. Run the ansible playbook to provision the VMs

ansible-playbook -i inventory.yml provision.yml

Alternatively you can use directly the run.sh script:

./run.sh

Note: the creation of the VMs and the installation of the kubernetes stack can take some time (~ 10-12 minutes on my laptop).

Tested with the following versions:

• Ansible 2.10.5 and 2.10.7
• Vagrant 2.2.7
• VirtualBox 6.0.12
• macOS Catalina 10.15.7

Don't forget to destroy the vagrant VM once done with your tests.

vagrant destroy
rm -rf .vagrant

Example:

Different Kubernetes files are available in the /root/files directory of the master node.

• deployment-nginx.yaml --> nginx deployment (3 replicas running on port 80)
• service-nginx.yaml --> nginx service (with nodeport 30080)
• manual-scheduling-nginx.yaml --> nginx pod to run on a specific node (node2)
• replicaset-nginx.yaml --> replicaset of nginx pods (3 replicas)

On the Kubernetes master, we can deploy the deployment and service definition file with the following commands:

root@master:~# cd files/
root@master:~/files# kubectl apply -f deployment-nginx.yaml 
deployment.apps/nginx created
root@master:~/files# kubectl apply -f service-nginx.yaml 
service/nginx created

The service and the pods should be ready:

root@master:~# kubectl get all
NAME                         READY   STATUS    RESTARTS   AGE
pod/nginx-7db75b8b78-5tp9v   1/1     Running   0          4m46s
pod/nginx-7db75b8b78-7kmb7   1/1     Running   0          4m46s
pod/nginx-7db75b8b78-hljqh   1/1     Running   0          4m46s

NAME                 TYPE        CLUSTER-IP     EXTERNAL-IP   PORT(S)        AGE
service/kubernetes   ClusterIP   10.96.0.1      <none>        443/TCP        19m
service/nginx        NodePort    10.96.66.198   <none>        80:30080/TCP   83s

NAME                    READY   UP-TO-DATE   AVAILABLE   AGE
deployment.apps/nginx   3/3     3            3           4m46s

NAME                               DESIRED   CURRENT   READY   AGE
replicaset.apps/nginx-7db75b8b78   3         3         3       4m46s

You can then access the Nginx welcome page by visiting either of the following URL:

• http://192.168.84.2:30080/
• http://192.168.84.3:30080/
• http://192.168.84.4:30080/