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Showing posts from 2016

Using Helm to install Traefik as an Ingress Controller in Kubernetes

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That was a mouthful of a title...Hope this post lives up to it :)

First of all, just a bit of theory. If you want to expose your application running on Kubernetes to the outside world, you have several choices.

One choice you have is to expose the pods running your application via a Service of type NodePort or LoadBalancer. If you run your service as a NodePort, Kubernetes will allocate a random high port on every node in the cluster, and it will proxy traffic to that port to your service. Services of type LoadBalancer are only supported if you run your Kubernetes cluster using certain specific cloud providers such as AWS and GCE. In this case, the cloud provider will create a specific load balancer resource, for example an Elastic Load Balancer in AWS, which will then forward traffic to the pods comprising your service. Either way, the load balancing you get by exposing a service is fairly crude, at the TCP layer and using a round-robin algorithm.

A better choice for exposing your Ku…

Kubernetes resource graphing with Heapster, InfluxDB and Grafana

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I know that the Cloud Native Computing Foundation chose Prometheus as the monitoring platform of choice for Kubernetes, but in this post I'll show you how to quickly get started with graphing CPU, memory, disk and network in a Kubernetes cluster using Heapster, InfluxDB and Grafana.

The documentation in the kubernetes/heapster GitHub repo is actually pretty good. Here's what I did:

$ git clone https://github.com/kubernetes/heapster.git
$ cd heapster/deploy/kube-config/influxdb

Look at the yaml manifests to see if you need to customize anything. I left everything 'as is' and ran:

$ kubectl create -f .
deployment "monitoring-grafana" created
service "monitoring-grafana" created
deployment "heapster" created
service "heapster" created
deployment "monitoring-influxdb" created
service "monitoring-influxdb" created

Then you can run 'kubectl cluster-info' and look for the monitoring-grafana endpoint. Since the monitor…

Running an application using Kubernetes on AWS

I've been knee-deep in Kubernetes for the past few weeks and to say that I like it is an understatement. It's exhilarating to have at your fingertips a distributed platfom created by Google's massive brain power.

I'll jump right in and talk about how I installed Kubernetes in AWS and how I created various resources in Kubernetes in order to run a database-backed PHP-based web application.

Installing Kubernetes

I used the tack tool from my laptop running OSX to spin up a Kubernetes cluster in AWS. Tack uses terraform under the hood, which I liked a lot because it makes it very easy to delete all AWS resources and start from scratch while you are experimenting with it. I went with the tack defaults and spun up 3 m3.medium EC2 instances for running etcd and the Kubernetes API, the scheduler and the controller manager in an HA configuration. Tack also provisioned 3 m3.medium EC2 instances as Kubernetes workers/minions, in an EC2 auto-scaling group. Finally, tack spun up a t…