Tag: show me

Total 12 Posts
kubernetes, show me

Installing Kubernetes Dashboard per Namespace

Even though I'm not Kubernetes Dashboard user, I understand why for most people this is the easiest way to interact with their apps running on top of Kubernetes. If you are interacting with it daily or managing the cluster itself, you are probably more fine with CLI aka kubectl. Kubernetes Dashboard is easy to install, but you might want to have it per namespace to limit what users can do. Let's see how to install and configure it for this ...

show me

An Easy Way to Track New Releases on GitHub

As a software developer, you need to keep track of many projects/tools hosted on GitHub. While GitHub has a watch feature, I found it too noisy. I open GitHub notifications once in a year, or maybe less. If you like GitHub notifications, great, you can watch a repo only for releases; they made this possible two months ago. This blog post probably doesn't make any sense for you then.However, I don't want to get a notification on new ...

kubernetes, show me

Kubernetes API Resources: Which Group and Version to Use?

Kubernetes uses declarative API which makes the system more robust. But, this means that we create an object using CLI or REST to represent what we want the system to do. For representation, we need to define things like API resource name, group, and version. But users get confused. The main reason for the confusion is that we as humans are not good at remembering things like this. In one deployment definition you could see this apiVersion: apps/v1beta2, and ...

kubernetes, show me

How to Run Dev.to on Kubernetes

Recently I was checking Dev.to community. I must say, I really like how the application looks, clean and simple. And more important I like the community there. I also started to republish some posts because I want to show Kubernetes to the larger audience, preferably developers. But, any time I check something new I get some new ideas. This time I saw that Dev.to is open source and thought, it would be pretty interesting for people to see ...

kubernetes, show me

Kubernetes Add-ons for more Efficient Computing

I will say that "starting" a Kubernetes cluster is a relatively easy job. Deploying your application to work on top of Kubernetes requires more effort especially if you are new to containers. For people that worked with Docker this can also be a relatively easy job, but of course, you need to master new tools like Helm for example. Then, when you put all together and when you try to run your application in production you will find out there ...

kubernetes, show me

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 ...

kubernetes, persistent storage, show me

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 ...

kubernetes, show me

Learn How to Troubleshoot Applications Running on Kubernetes

I'm writing a lot of about Kubernetes for a few months already. I like the idea of cloud-native applications. There are a lot of easily installable applications for Kubernetes out there. One of the biggest resources of "Kube ready" applications is Kubeapps Hub. The list keeps growing really fast. So, all this is a good thing. But, there is also a small problem. People run some commands that they don't quite understand. It can be a copy/paste ...

kubernetes, show me

Package Kubernetes Applications with Helm

Writing a bunch of Kubernetes configuration files is not so much fun. For a few containers, you will end up with 10+ yaml files. Maintaining them is only one issue, but running in different environments or using the same files for CI/CD is a nightmare. You can always use some bash tricks to replace some values, but that is a bad practice. Here is where Helm comes into place. I should mention that there is also another interesting tool ...

kubernetes, show me

Kubernetes Environment Variables

When building your application stack to work on Kubernetes, the basic pod configuration is usually done by setting different environment variables. Sometimes you want to configure just a few of them for a particular pod or to define a set of environment variables that can be shared by multiple pods. Later is usually done by creating a ConfigMap as a shared resource. Instead of specifying each environment variable individually we can reference the whole config map. Set Environment Variables To ...

kubernetes, show me

Stateful Applications on Kubernetes

Kubernetes and stateless applications work just out of the box. You can create a replicated application fast. The stateless application doesn't store any data, and simple load balancing does the job when it comes to scaling it. However, if you want to run any application that stores the data somewhere, you care about the order how the application starts or you want a stable hostname and network ID, then we are talking about the stateful applications and in Kubernetes world ...

aws, show me

Terraform and AWS Spot Instances

Terraform is my tool of choice for cloud provisioning. The difference compared to the similar tools for cloud provisioning is that Terraform saves the state. Terraform supports AWS and can provision spot instances also. Spot instances are great to save some money in the cloud. They could be used for any service, but it is really hard to manage stateful services like databases. If you have a stateless service spot instances are a great choice. You need to automate spot ...