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Alen Komljen

Total 40 Posts

All things DevOps.

  • Sarajevo
serverless

Serverless: The New Way of Thinking

I'm preparing the first CNCF meetup in Sarajevo and thinking about what would be interesting to present at the first meetup. Of course, I will talk a little bit about CNCF in general, but I want something interesting for the second talk. Something that will bring more developers to future CNCF meetups. And, as you can guess it will be about Serverless. I'm not expert in this area, but I like the idea. My colleague, Andan Rahic loves to write ...

monthly update

Monthly Update 3

It took me a while to write this update. A lot of is going on in my private life and it is hard to find some free time to write. But, I enjoy writing and sharing. There are some great and important things I want to share in this monthly update. My Updates A few weeks ago I created Cloud Native meetup group in Sarajevo. In Sarajevo we don't have any DevOps or Cloud Native related meetups. But, I know ...

kubernetes, autoscaling, aws

Kubernetes Cluster Autoscaling on AWS

Running a production Kubernetes cluster is not that easy. Also, unless you use cloud resources smart, you will be spending much money. You only want to use resources that are needed. When you deploy Kubernetes cluster on AWS, you define min and max number of instances per autoscaling group. You want to watch Kubernetes cluster and on insufficient resources to scale up. Also to scale down when you have underutilized nodes. The piece of software that will help you with ...

kubecon, cloudnativecon

KubeCon and CloudNativeCon Special - Copenhagen 2018

Unfortunately, I missed KubeCon and CloudNativeCon conference in Copenhagen last week and a chance to meet all great people. I guess I will have to wait for another one. Luckily all presentations are online, so I will be able to catch up. Kubernetes is the important part of Cloud Native Computing and as Aparna Sinha mentioned Kubernetes is second to Linux in the number of PRs and issues. Those are the big numbers and I'm happy to be part of ...

kubernetes, descheduler

Meet a Kubernetes Descheduler

The kube-scheduler is a component responsible for scheduling in Kubernetes. But, sometimes pods can end up on the wrong node due to Kubernetes dynamic nature. You could be editing existing resources, to add node affinity or (anti) pod affinity, or you have more load on some servers and some are running almost on idle. Once the pod is running kube-scheduler will not try to reschedule it again. Depending on the environment you might have a lot of moving parts. In ...

monthly update

Monthly Update 2

Here is the second post of my monthly update series. Today is a day 1 of KubeCon + CloudNativeCon conference in Copenhagen, Denmark, and all eyes will be on it for a few days. Unfortunately, I will not be there, but I will track all the events and write about it during the next few weeks. Before that, I will share some news that I found interesting and important. My Updates As usual, I will start with my updates. In April ...

kubernetes, efk, monitoring, logs

Get Kubernetes Logs with EFK Stack in 5 Minutes

Last week I wrote about getting Kubernetes cluster metrics with Prometheus. Metrics are only one part of the story. Logs are essential as well, and luckily we have a great set of tools that will help us to create simple and easy logging solution. In this post, I will show you how to start monitoring Kubernetes logs in 5 minutes with EFK stack (Elasticsearch, Fluent Bit, and Kibana) deployed with Helm and Elasticsearch operator. Previous post Just blogged: Get #Kubernetes ...

kubernetes, prometheus, monitoring, metrics

Get Kubernetes Cluster Metrics with Prometheus in 5 Minutes

To have a Kubernetes cluster up and running is pretty easy these days. However, when you start to use it and deploy some applications, you might expect some issues over time. Kubernetes being a distributed system is not easy to troubleshoot. You need a proper monitoring solution, and because the Prometheus is CNCF project as Kubernetes, it is probably the best fit. In this post, I will show you how to get the Prometheus running and start monitoring your Kubernetes ...

kubernetes, persistent storage

Kubernetes Persistent Volumes with Deployment and StatefulSet

I get many questions about Kubernetes and persistence. Of course, persistence is essential for stateful apps. We often say that for stateful apps you need to use StatefulSet and for stateless apps a Deployment. It doesn't mean that you couldn't run stateful apps using deployments with persistent volumes. For example, the official MySQL Helm chart is using deployment. So, it can be done, but users get confused about this. What is the deal? When should you use deployment and when ...

monthly update

Monthly Update 1

It is impossible for me to try every piece of technology that comes out and to write about it. I had this idea for a while and decided to start writing monthly updates. Each update will have a few topics that I found interesting. Sometimes there will be things that I was working on, some exciting news, tools that are interesting and related to above. Feel free to send suggestions or to comment on something. Let me know if you ...

kubernetes, drone, ci/cd, pipeline

Set Up a Drone CI/CD Pipeline with Kubernetes

I like to say that continuous delivery or CD is the most important part of Cloud Native. There are so much great tools out there and you need to pick up the right ones. A few weeks ago I was writing almost about the same topic, only with Jenkins. While the Jenkins is the most used CI/CD tool, not every team is happy with it. Jenkins has a huge number of plugins and the great set of features, but ...

kubernetes, ceph, persistent storage

Using Existing Ceph Cluster for Kubernetes Persistent Storage

I wrote about Rook storage a few weeks ago, but maybe you already have Ceph cluster running in your datacenter. Or you prefer to use Ceph on separate nodes and without Kubernetes. Also, currently Rook is alpha software and not ready for production use. I would assume that this large Ceph cluster if you have one, is also used for other services outside Kubernetes. Whatever is the case it is simple to connect Ceph and Kubernetes together to provision persistent ...