These next steps provide a simple introduction to the idea of putting two containers in a Pod to achieve the sidecar pattern. The primary advantage of sidecars is the separation of concerns. Each container is highly cohesive in terms of responsibilities, yet they work together to provide a single solution.
With a Kubernetes cluster and a CLI tool called kubectl, a few steps will get an Nginx web server running along with its sidecar.
You will learn how:
- to use the basics of the kubectl CLI tool,
- to install Nginx on Kubernetes,
- containers are deployed as Deployments in Pods,
- a Service can provide access to a replication of Pods,
- two containers can work together to provide a solution,
- two containers can share information through a shared file mount.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy, and HTTP cache. The software was created by Igor Sysoev and first publicly released in 2004. A company of the same name was founded in 2011 to provide support and Nginx plus paid software.
Nginx is free and open-source software, released under the terms of a BSD-like license. A large fraction of web servers use NGINX, often as a load balancer. -- Wikipedia
You now understand two different techniques for starting a container on Kubernetes. Nginx is commonly used for serving up web content and as you can see is easy to start on Kubernetes. There are thousands of other containers that can easily be started with these same basic steps.
With these steps you have learned how:
- ✔ to use the basics of the kubectl CLI tool,
- ✔ to install Nginx on Kubernetes,
- ✔ containers are deployed as Deployments in Pods,
- ✔ a Service can provide access to a replication of Pods,
- ✔ two containers work together to provide a solution,
- ✔ two containers share information through a shared file mount.
Your Kubernetes Cluster
For this scenario, Katacoda has just started a fresh Kubernetes cluster for you. Verify it's ready for your use.
kubectl version --short && \
kubectl get componentstatus && \
kubectl get nodes && \
The Helm package manager used for installing applications on Kubernetes is also available.
helm version --short
You can administer your cluster with the
kubectl CLI tool or use the visual Kubernetes Dashboard. Use this script to access the protected Dashboard.