Test K8s project

Prerequisites

To spin up the k8s cluster the next tools have to be installed:

Hashicorp's Vagrant, version >= 2.2 - to create & provision the nodes as virtual machines.
Oracle's VirtualBox, version 5.1 as the Vagrant's provider - to run the virtual mashines.

Testing platform

a PC workstation with 4xCPU / 8 GB RAM / 256 GB SSD

Testing application

Simple http 'hello world' for load balancer testing - taken here

Network topology

The cluster is being launched in a private (host-only) Virtualbox network. It's eth1 interface on the cluster's vms.

IP addresses

master - 172.28.128.2
node1 - 172.28.128.3

Workflow

Launching the k8s cluster - it takes up to 10 minutes on the testing platform:

vagrant up

SSHing into the cluster's master node:

$ vagrant ssh master
vagrant@master:~$ sudo su -
root@master:~#

Getting the list of the cluster's nodes:

root@master:~# kubectl get nodes
NAME     STATUS   ROLES    AGE   VERSION
master   Ready    master   21m   v1.13.3
node1    Ready    <none>   18m   v1.13.3

Deploying the helloworld-http app's stack (service+deployment+ingress controller+ingress) - it takes to 5 minutes till the all pods start:

root@master:~# /vagrant/k8s-helloworld-app-deployment.sh 
Creating simple HTTP web application...
...
Deploying Nginx ingress controller...
...
Creating the ingress for the simple HTTP app...
..
Determining the NodePort's port...
The service's HTTPS port is: 32377
Now you can access the app's pods with such query:
curl -k https://172.28.128.2:32377/

Checking the pods placement:

root@master:~# /vagrant/k8s-check-pod-node-affinity.sh 

Checking the placement for pods with with label: helloworld-http ...

POD NAME                                NODE NAME
helloworld-http-6d6ff59b6d-cg76w        master
helloworld-http-6d6ff59b6d-vp799        node1

Checking the load balancing works correctly:

vagrant@master:~$ exit

$ curl -k https://172.28.128.2:32377/
<html><head><title>HTTP Hello World</title></head><body><h1>Hello from helloworld-http-6d6ff59b6d-vp799</h1></body></html

$ curl -k https://172.28.128.3:32377/
<html><head><title>HTTP Hello World</title></head><body><h1>Hello from helloworld-http-6d6ff59b6d-cg76w</h1></body></html

Traffic capturing

Deploying a sniffering pod running tcpdump inside (the image):

root@master:~# /vagrant/k8s-sniffer-deployment.sh
Deploying a sniffer pod into host network...
pod/sniffer-pod created
...

Now you can ssh into sniffer-pod pod and read all network traffic with commands:

# kubectl exec -it sniffer-pod sh
$ tcpdump -r /data/dump*

ironreality/k8s-simple-http-app