An Introduction to Kubernetes
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This document introduces Kubernetes, a platform for hosting Docker containers in a clustered environment, detailing its architecture, components, and features such as load balancing and auto-healing. It explains the role of Linux containers, Docker, and provides insights into Kubernetes' key concepts like pods, labels, and the API server. Additionally, it includes references and links for further exploration of virtualization and container technology.
An Introduction to Kubernetes
- 1. An Introduction to Kubernetes Imesh Gunaratne Product Lead, WSO2 Private PaaS Committer & PMC Member, Apache Stratos
- 2. Agenda ā Linux Containers ā Docker ā Kubernetes ā Kubernetes Architecture ā Kubernetes Demo
- 4. Linux Containers Linux Container Brief for IEEE WG P2302, Boden Russell
- 5. Linux Containers An operating systemālevel virtualization method for running multiple isolated Linux systems (containers) on a single control host. http://en.wikipedia.org/wiki/LXC
- 6. Linux Kernel Features used by Linux Containers ā Namespaces (mnt, pid, net, ipc, uts/hostname, user ids) ā cgroups (cpu, memory, disk, i/o - resource management) ā AppArmor, SELinux (security/access control) ā seccomp (computation isolation) ā chroot (file system isolation) http://www.slideshare.net/imesh/evoluation-of-linux-container-virtualization
- 7. LXC Engine: A Hypervisor for Containers Linux Container Brief for IEEE WG P2302, Boden Russell
- 8. More about Linux Containers https://linuxcontainers.org
- 10. Docker ā A platform for managing Linux Containers ā Began as an open-source implementation of the deployment engine which powers dotCloud ā Started in March, 2013 ā Provided an easy to use API and powerful container image management features ā Attracted the community very fast https://github.com/docker/docker/blob/master/README.md
- 11. Docker is built on ā cgroup and namespacing capabilities of the Linux kernel ā Go programming language (written in Go) ā Docker Image Specification (for container image management) ā Libcontainer Specification (namespaces, filesystem, resources, security, etc) https://github.com/docker/docker/blob/master/README.md
- 12. Virtual Machines Vs Docker https://www.docker.com/whatisdocker/
- 13. Docker Architecture Enterprise Docker, Adrien BLIND, Aurelien GABET, Arnaud MAZIN
- 15. Docker - Hello World # Get one base Docker image >docker pull ubuntu # List Docker images available >docker images # Run hello world >docker run ubuntu:14.04 echo "hello world" Docker Paris Meetup, Victor Vieux, dotCloud Inc
- 16. Detached mode # Run hello world in detached mode (-d) >docker run -d ubuntu sh -c "while true; do echo hello world; sleep 1; done" # Get containerās ID >docker ps # Attach to the container >docker attach <container-id> # Stop/start/restart the container >docker stop <container-id> Docker Paris Meetup, Victor Vieux, dotCloud Inc
- 17. Problems with standalone Docker Load Balancer Docker Containers Docker Host ā Running a server cluster on a set of Docker containers, on a single Docker host is vulnerable to single point of failure!
- 18. Kubernetes
- 19. Kubernetes ā Kubernetes is a platform for hosting Docker containers in a clustered environment with multiple Docker hosts ā Provides container grouping, load balancing, auto-healing, scaling features ā Project was started by Google ā Contributors == Google, CodeOS, Redhat, Mesosphere, Microsoft, HP, IBM, VMWare, Pivotal, SaltStack, etc
- 20. Key Concepts of Kubernetes ā Pod - A group of Containers ā Labels - Labels for identifying pods ā Kubelet - Container Agent ā Proxy - A load balancer for Pods ā etcd - A metadata service ā cAdvisor - Container Advisor provides resource usage/performance statistics ā Replication Controller - Manages replication of pods ā Scheduler - Schedules pods in worker nodes ā API Server - Kubernetes API server
- 21. Kubernetes Architecture Overlay Network: 10.1.0.0/16 (Flannel, Open vSwitch, etc) Kubernetes Master Kubernetes Minion 1 Kubernetes Minion 2 Kubernetes Minion n Service Network: 172.17.8.0/24 etcd Docker Registry API Replication Controllers Scheduler Kubelet Proxy cAdvisor Pods Docker A Docker B
- 22. Kubernetes Master Kubernetes Master Kubelet Info Service API Scheduler Replication Controllers
- 23. Kubernetes Minion (Worker Node) Kubernetes Minion Kubelet Proxy Pod 1 Pod 2 Pod n cAdvisor ContainersContainersContainers ContainersContainersContainers ContainersContainersContainers Kubernetes Services Kubernetes Services Kubernetes Services
- 25. Kubernetes Demo
- 26. References ā http://en.wikipedia.org/wiki/Virtualization ā http://en.wikipedia.org/wiki/Hypervisor ā http://en.wikipedia.org/wiki/LXC ā http://www.cs.ucsb.edu/~rich/class/cs290- cloud/papers/lxc-namespace.pdf ā http://en.wikipedia.org/wiki/Cgroups ā http://en.wikipedia.org/wiki/AppArmor ā http://en.wikipedia.org/wiki/Security-Enhanced_Linux ā http://www.lorien.ch/server/chroot.html
- 27. References ā SELinux for Everyday Users, PaulWay ā http://en.wikipedia.org/wiki/Seccomp ā http://en.wikipedia.org/wiki/Chroot ā Linux Container Brief for IEEE WG P2302, Boden Russell ā http://kubernetes.io/ ā https://www.youtube.com/watch?v=Fcb4aoSAZ98 ā http://www.slideshare.net/enakai/architecture- overview-kubernetes-with-red-hat-enterprise-linux-71