IBM 开源技术微讲堂容器技术与微服务系列

Transcription

1 IBM 开源技术微讲堂容器技术与微服务系列 第五讲 Kubernetes 简介 h,p://ibm.biz/opentech- ma 1

2 容器技术和微服务 系列公开课 每周四晚 8 点档 Docker 一种全新的 工作 方式 容器编排 工具 Docker Swarm 数据中 心操作系统的内核 Apache Mesos 大数据 Web 服务 CI/CD: 一个都不能少 深 入理解 Mesos 的资源调度及使 用案例 Kubernetes 简介 各取所 长 Kubernetes on Mesos 微服务平台端到端业务解决 方案 事件驱动 无服务器平台 OpenWhisk 2

3 讲师介绍 程启健 IBM中国开发中 心电 子商务开发部 门架构师 2015年 至今负责电 子商务系统的微服务化和 容器化 工作 3

4 议程 IntroducJon to Kubernetes Build your Microservice applicajon with Kubernetes 4

5 What is Kubernetes? Kubernetes is an open- source plaoorm for automajng deployment, scaling, and operajons of applicajon containers across clusters of hosts, providing container- centric infrastructure. With Kubernetes, you are able to quickly and efficiently respond to customer demand: Deploy your applicajons quickly and predictably. Scale your applicajons on the fly. Seamlessly roll out new features. OpJmize use of your hardware by using only the resources you need Kubernetes is: portable: public, private, hybrid, mulj- cloud extensible: modular, pluggable, hookable, composable self- healing: auto- placement, auto- restart, auto- replicajon, auto- scaling 5

6 Kubernetes Architecture 6

7 Make it simple Kubectl master User worker nodes worker nodes 7

8 K8s Node Worker/Minion kubelet The kubelet manages pods and their containers, their images, their volumes, etc. kube- proxy Each node also runs a simple network proxy and load balancer. This reflects services as defined in the Kubernetes API (apiserver) on each node and can do simple TCP and UDP stream forwarding (round robin) across a set of backends. 8

9 K8s Node Master API Server Serves up the Kubernetes API Processes REST operajons, validates them, and updates the corresponding objects in etcd. Controller Manager Server All other cluster- level funcjons are currently performed by the Controller Manager Scheduler Server The scheduler binds unscheduled pods to nodes via the /binding API. Etcd API Server Scheduler Controller Manager Kubernetes Master 9

10 Components in K8s Namespace s Pod ReplicaJon Controller/ReplicaJon Set Service Persistent Volume Persistent Volume Claim 10

11 Pods A pod is a co- located group of containers Shares Volume Network Node 1 Pod1 Pod2 11

12 Replica>on Controller A replicajon controller ensures that a specified number of pod replicas are running at any Jme. Scaling up/down Handle re- creajon of a pod Master ReplicaJon controller Pod1 Pod2 Node 1 Node 2 Pod1 Pod2 12

13 Service A service defines how to access a set of pods And more Service Discovery Load balancer Worker Node Service IP Kubernetes proxy Kubernetes API Server Expose your applicajon to external world Node Port Load Balancer Endpoint pod :80 Endpoint pod :80 Endpoint pod :80 13

14 Persistent Volume Manage the storage of the container PV:Resources in the cluster. PVC: Requests for those resources Persistent Volume Types: GCEPersistentDisk Node 1 AWSElasJcBlockStore NFS CephFS Cinder Pod1 Pod2 14

15 Labels Labels are key/value pairs that are a,ached to objects, such as pods. Define Label Selectors to idenjfy a set of objects 15

16 Feature Resource management MulJ- Level Resource Limits Resource Quota Resource request & limits 16

17 Feature Rolling update Avoid service interrupjon Update Pod one by one, and update service Service Env=Pre, App=Portal Env=Prod, App=Portal Node Cluster 容器 容器 Env=Pre Env=Prod Env=Canary Env=Pre Env=Prod Env=Prod Env=Prod Env=Prod App=Portal App=Portal App=Portal App=Portal App=Portal Release=1.1 Release=1.0 Release=1.1 Release=1.0 Release=1.0 Release=1.1 Release=1.0 Release=1.1 Release=1.0 Release=1.1 17

18 Microservice Images from: h,ps:// to- microservices/ 18

19 Service Registra>on and Service Discovery Requirement: Dynamically assigned network locajon Kubernetes prefer pa,ern Server- side discovery K8s feature: Service Load balancer and Service Registry DNS ReplicaJon controller Health checker 19

20 Centralize configura>on SoluJon: Spring Cloud Config Consul & Consul- Template Etcd/ZK & Confd, Disconf NeOlix Archaius ConfiguraJon ConfiguraJon Store in Kubernetes Config Map App 1 App 2 App 1 App 2 20

21 Monitor Kubernetes Heapster Other opjons: Prometheus Kube- apiserver Node kubelet cadvisor Node kubelet cadvisor 21

22 Logging in Kubernetes Fluentd + ElasJc Search + Kibana Node 1 Pod1 Daemon Set Fluentd ElasJc Search Logging Folder Log File Log File Log File 22

23 Mul>- tenant Support Base on Namespaces Resource isolajon in Network Service Config map. 23

24 IBM 开源技术微讲堂容器技术与微服务系列 第五讲完 h,p://ibm.biz/opentech- ma 24