Kubernetes Nedir?
- 1. What is Kubernetes ? Ahmet Üstün ahmetustun@comind.ai 1
- 2. What does “Kubernetes” means ? Kubernetes = Greek for “pilot” or “helmsman of a ship” 2
- 3. Kubernetes A Production-Grade Container Orchestration System Google-grown, based on Borg and Omega, systems that run inside of Google right now and are proven to work at Google for over 10 years. Google spawns 2 billion containers per week with these systems. Created by three Google employees initially during the summer of 2014 Hit the first production-grade version v1.0.1 in July 2015. Have continually released a new minor version every three months since v1.2.0 in March 2016. v1.8.0 was just released 28th September 2017. 3
- 4. So what does Kubernetes actually do ? One thing: Abstract away the underlying hardware. Abstract away the concept Node. Principle: Manage your applications like Cattle (generic, bulk operations) instead of like Pets (every operation is customized with care and love for the individual) You (the admin) declares the desired state, Kubernetes' main task is to make the desired state the actual state. 4
- 5. So what does Kubernetes actually do ? A system for container management in a clustered environment. Multiple cloud and bare-metal environments. Multiple container engines, mainly based on Docker. Provides grouping, load balancing, scaling and scheduling features. Manages applications, not machines 5
- 6. Kubernetes’ popularity KUBERNETES MESOS DOCKER SWARM CLOUD FOUNDRY OPENSTACK Google Search interest over time in the 1.10.2012-1.10.2017 timespan 6
- 8. Master Components API Server: The main management endpoint for cluster (RESTful interface) Controller Manages: Handles replication management Scheduler Server: Assigns workload to specific nodes etcd: A distributed key-value store for sharing configuration 8
- 9. Node Components Docker: A container system which runs on a dedicated network Kubelet: Is responsible for the communication with master server Proxy: Used for network forwarding and load balancing 9
- 10. Work Units: POD 10 POD = A collocated group of containers (one-to-many) with shared resources. e.g. network, volumes. It can be viewed as a "logical host".
- 11. Work Units: LABELS and SELECTORS 11 LABELS and SELECTORS = Arbitrary metadata that represent identity for generic grouping mechanism - pods in a ReplicaSet - pods in a Service
- 12. Work Units: SERVICES 12 SERVICES = An interface to a group of containers, which acts as load-balancer and provides an abstraction layer - no need to worry about containers location. (+ External Services)
- 13. Work Units: REPLICA SET 13 REPLICA SET = Ensures that the number of desired pods "replicas" are running at any time.
- 14. Work Units: DEPLOYMENT 14 DEPLOYMENT = Declarative way to describe the desired state of the application (pods, replica sets).
- 15. Work Units: DAEMON SETS 15 DAEMON SETS = Way to run a Pod on every node?
- 16. Work Units: DAEMON SETS 16 CONFIG MAP and SECRET = Provides one interface to manage app configuration & secrets 12-factor says config comes from the environment
- 17. Work Units: DAEMON SETS 17 HORIZONTAL AUTO SCALER = Automatically scale pods as needed - based on CPU utilization (for now) - custom metrics in Alpha
- 18. Work Units: PERSISTENT VOLUME 18 PERSISTENT VOLUME = Manage storage with its own lifecycle. +20 supported driver plugins: - Google Persistent Disk - Amazon ESB - Ceph ...
- 19. Networking 19
- 20. Networking 20
- 21. Kubernetes general view 21
- 22. Kubernetes manifest example 22 apiVersion: v1 kind: Service metadata: name: web-frontend spec: selector: app: webapp role: frontend ports: - port: 80 targetPort: 80 apiVersion: apps/v1beta2 kind: Deployment metadata: labels: app: webapp role: frontend name: web-frontend spec: replicas: 3 template: metadata: labels: app: webapp role: frontend spec: containers: - image: nginx:1.13.1 name: nginx ports: - containerPort: 80 name: http
- 24. Monitoring 24
- 25. Logging 25
- 26. Continuous Deployment/Integration with Kubernetes 26
- 27. Cluster Deployment 27 Minikube: https://github.com/kubernetes/minikube Kubeadm: https://kubernetes.io/docs/setup/independent/create-cluster-kubeadm/ Kubespray: https://github.com/kubernetes-incubator/kubespray Kops (Kubernetes Operations): https://github.com/kubernetes/kops
- 28. Kops Use Case 28