I just finished a webinar series about Kubernetes, and I just wanted to thanks a couple of people to make this happen. First thanks goes to my wife since he supported me by looking at our kids on her own during this webinar moments in Sundays! Second, thank you Serhat Can and Cloud & Serverless Turkey team for preparing and publishing event series week by week to notify audience, this wouldn’t be real without your help…
You can see all the materials I have used during webinar here
1. Kubernetes Hands-On #1: Kubernetes Installation, The Hard Way
In this session, we talked about k8s theory and explained k8s core components. After a reasonable explanation, we installed k8s cluster by using long way.
2. Kubernetes Hands-On #2: What is deployment, pod and service?
In this session, I tried to explained what is the idea behind k8s resources.
3. Kubernetes Hands-On #3: Volume And Configuration Management
You have deployment and wanted to inject some config or data into it? Then, this session is just for you.
4. Kubernetes Hands-On #4: Kubernetes Ingress and Network Policies
In this session, we talked about how you manage traffic within kubernetes environment or traffic between your k8s environment and public world. You will learn how to expose your application to outside in real world examples.
5. Kubernetes Hands-On #5: RBAC and Secret Management
Like every other systems, you can mange roles and assign them to specific identities, groups in k8s. In this session, we did hands on examples, and also showed you how to create secrets to store some confidential data.
6. Kubernetes Hands-On #6: Kubernetes Rolling Update Explained
You have application in production and now you wanted to deploy new version? In this session you will see ow to deploy something, update it, even roll-forward or roll-back to specific revision.
Being able to react to any kind of anomality on production environment is the key to success. Kubernetes has good features to let you revert your deployments back with a simple command. If you have ever heard following scenario within your company before, this session will be the medicine for you. “Payment microservice is in an unstable state after last deployment, what we can do?” “I realized that Cart service has incorrect version during the deployment is in half state, I need to revert them back…”
At the end of April 2018, I visited Amsterdam for a good reason. Visiting the good places that I couldn’t visited 3 years ago, and after filling that power, I just made a talk about Microservice Best Practices on Kubernetes. The event is handled by Booking, and I was very happy with their hospitality. Thank you again !
Let me provide brief summary of each topic I have mentioned on the event. You can see my slides here, if you are not so much patient 🙂
1. Glory of REST
Microservices are like humans, and they need to communicate with each other by using well structured interfaces. Richardson’s Maturity Model is a good reference to this
2. Power of HATEOAS
Hypermedia As The Engine Of Application State provides navigate-able resources that you will find all the informations within the response. Forget about trying to generate some links on different kind of client applications to navigate next resources by using previous one.
3. Distributed Configuration
When you switched to the Microservice Architecture, you will need to configure multiple services at the same time, that configs must be applied to applications in real-time, etc… Distributed configuration can be handled with Consul as key/value pair, git2consul for synchronizing configurations to Consul, and you may need to keep those configurations on a simple git project.
4. Client Code Generation
In order to communicate microservices, you may have 2 options at least to make inter service communications. If you are already using service discovery, you can think about Feign Client. Or else, you can use swagger-codegen to generate client library whenever you deploy your app to any kind of environment. Do not think about writing client libraries manually for your hundreds of microservices, just trigger a Jenkins job and take a REST!
5. Kubernetes Warm-up
You can create a k8s folder to keep your k8s resource definitions to use on deployment pipeline. A typical micro service may have deployment, service definition at least for deployment and exposing your application to the outside or at least to the load balancer
If you have kubernetes specifications within your project, you are ready to deploy your app by using Jenkins with a simple kubectl configuration within jenkins servers. In order to reduce complexity, you can use multi stage builds to build docker image to use in your k8s deployment.
Even you are in a stable environment like k8s, you need to track your infrastructure and application insights. To collect metrics, you can use Prometheus, and to serve them in a good dashboard, you can use Grafana. CoreOS team developed a good project that is called prometheus operator comes with a built-in kubernetes configurations. One click monitoring !
There are several types of logging architecture on kubernetes and I mainly focused on cluster level logging with daemon set agents. You can send your logs to logging backend like Elasticsearch to show on Kibana dashboard, or if you don’t want to maintain ELK stack, you can use https://humio.com/ for a fast centralized real-time logging and monitoring system. Just use their kubernetes integration
9.APM & Service Mesh
Monitoring and Logging may not help you all the time, you may need to see deeper insights about your application. When it comes to Microservice and Container world, Instana is a good choice to handle Tracings, Monitoring with a simple sensor integration. You can create your infrastructure map, see traces and spans for a request lifecycle, even you can see real time service requests on simple dashboard.
10. API Gateway
If you are planning to expose your services to the public, you definitely manage your APIs with an API Gateway to perform Authentication, Authorization, Rate Limiting, API Versioning, etc… I have used Tyk API Gateway to set this up in Kubernetes to route traffic to microservices after successfully validated by API Gateway.
11. Event Sourcing & CQRS
In a synchronous world, you can only change 1 object in 1 transaction at a time. When you switch to distributed systems, you need to use 2-phase commits in an extended architecture. Again, with this strategy, whenever you made an update to current state of an object, all the previous states will be gone. You can use Event Sourcing with asynchronous events stored in an event store like Apache Kafka, Hazelcast, etc… Also, you can separate read (query) and write (command) in order to handle events asynchronously and populate desired views on database to serve it via query later.
Hope above sections would be a good reference for your next Microservice Architecture design.
In this session, we will cover how an external access to the internal cluster can be architected in Kubernetes environment. Beside some theoretical information, we will apply some production-ready dojos. The outline will be;
What is Ingress?
Ingress Operations on Production Environment
Isolated and Non-Isolated Pods with Network Policies
In a typical Kubernetes cluster, you can do lots of things to make your DevOps mindset become true. If you plan to extend your from personal one to enterprise one, you need to apply some authorization rules to restrict some operations according to needs. In this session, you will see a do a kubernetes dojo especially for authorization and secret management.
What would you do if you needed to upgrade your machine types on production environment on Google Cloud? If you are using Google Kubernetes Engine, it is a piece of cake. I have upgraded machine types from n1-standard-1 to n1-standard-2 for all of the kubernetes cluster nodes and you can see my adventure in following video.
Application configuration is one of the most important operations of a production ready environment. Kubernetes lets us create and manage these configurations in several ways. Additionally, we need to share application specific data in a clustered environment on cloud or on premise. In this webinar, you can see kubernetes dojo for production ready cases.
In this session, we had a look at the some of the most important concepts of Kubernetes; Services, Pods, Deployments in order to understand the application lifecycle in a typical Kubernetes environment. Some of the topics covered are below;
– Creating Deployment – Single and Multi-Container Concept in Deployment – Monitoring, Debugging Pods – Service Types – Exposing Services to Internet – Manage Environment Variables of Deployment – Service-to-Service Communication
In this webinar, I have provided to mention about Google Cloud Platform basics and applied some operations with both Google Cloud Console and Google Cloud SDK. If you want to spin up a VM instance and install Jenkins, grab your coffee and have some fun for a couple of minutes 🙂