Deploying your first Micro-Service Application to Kubernetes

Kubernetes is a very powerful container orchestration platform that is quickly gaining traction and gives you lots of benefits in deploying, running and scaling your microservice web application. But it has also a steep learning curve. In this workshop you will deploy and scale your first application which consists of multiple Micro-Services to Kubernetes and learn how you can use Persistent Storage. If you want to not just watch, but also program along yourself, have Git, Docker and the Kubernetes CLI kubectl as well as a IDE or Text Editor of your choice installed on your system.

Transcript

1. @BastianHofmann Deploying your first Micro-Service Application to Kubernetes Bastian Hofmann
3. Agenda for today
4. Kubernetes Basics
5. Deploying an application
6. Load Balancing
7. Persistent Storage
8. Configuration Management
9. Environment Management
10. Service Discovery
11. Service Meshes
12. Monitoring
13. Debugging
14. Logging
15. (Auto) Scaling
17. Container orchestration platform
18. Deploy, run and scale your services in isolated containers
19. Why containers?
20. Services run in isolation
21. Everything needed to run a service in one image
22. Make things …
23. Easier to deploy
24. Easier to upgrade system dependencies
25. Easier to develop
26. Easier to scale
27. Better resource usage
28. #safeThePlanet
29. No vendor lock in
30. Standardized APIs
31. Runs on
32. Your laptop
34. Bare metal
35. Cloud Providers
36. And if you don't want to install and maintain Kubernetes yourself
37. Managed Kubernetes
39. Benefits of Managed Solutions
40. Easy upgrades
41. Easy scaling
42. Features
43. Load Balancing
44. Distributed Persistent Storage
45. Some do offer
46. Backups
47. Hyperscaling
48. Premium support
49. Carefree Usage & pro-active monitoring
50. You can focus on what's important
51. Let’s define some core concepts and terminology first
52. Kubernetes Cluster
53. • A docker image built from a Dockerfile that contains everything a service needs to run Image
54. • A container runs a docker image. • Only 1 process can run inside of a container Container
55. • A group of 1 or more containers • Same port space • Ports are not accessible from outside of the pod Pod
56. • Defines and manages how many instances of a pod should run Replica Set
57. • Manages updates and rollbacks of replica sets Deployment
58. • Makes a port of a pod accessible to other pods Service
59. • Makes a service accessible to the outside of Kubernetes Ingress
60. • A physical server • Containers get distributed automatically Node
61. • Configuration that can be mounted inside of a container ConfigMap
62. • Volumes can be mounted into a container to access a ConfigMap, Secret or a folder on the host Volumes
63. • Dedicated environment to deploy services in Namespaces
64. DaemonSets, CronJobs, StatefulSets, ...
65. Everything is a resource
66. You interact with Kubernetes by creating, receiving, updating and deleting resources
67. Kubernetes has controllers to listen on these interactions and get the cluster in the desired state
68. kind: Deployment apiVersion: extensions/v1beta1 metadata: name: symfony-demo spec: template: spec: containers: - name: symfony-demo image: symfony-demo:1.1.0 ports: - containerPort: 80
69. $ kubectl apply -f deployment.yaml
70. $ kubectl get deployments NAME DESIRED CURRENT UP-TO-DATE AVAILABLE AGE symfony-demo 1 1 1 1 21h
71. $ kubectl get deployment symfony-demo -o yaml apiVersion: extensions/v1beta1 kind: Deployment metadata: annotations: ... spec: ... template: ... spec: containers: - name: symfony-demo image: symfony-demo:1.1.0
72. $ kubectl delete deployment symfony-demo
73. The Kubernetes API can be extended with additional Resources and Controllers
74. CustomResourceDefinitions
75. Certificate, Backup, Restore, MySQLCluster, Function, ...
76. To interact with Kubernetes
77. kubectl
78. $ kubectl get pods
79. NAME READY STATUS RESTARTS AGE kubernetes-dashboard-5b5bf59977-t9xb9 1/1 Running 2 9d nginx-ingress-controller-5549f5597c-97kcw 0/1 Running 2 9d nginx-ingress-default-backend-564d9d9477-tmnnr 1/1 Running 4 9d mysql-556c9b5bcb-5jdrt 1/1 Running 1 8d symfony-demo-5b75f5fc6-c7wr9 1/1 Running 0 8d symfony-demo-5b75f5fc6-jg8n4 1/1 Running 23 8d
80. REST API
81. $ kubectl proxy --port=8080 $ curl http://localhost:8080/api/v1/namespaces/default/ pods { "kind": "PodList", "apiVersion": "v1", "metadata": { "selfLink": "/api/v1/namespaces/default/pods", "resourceVersion": "336834" }, "items": [ { "metadata": { "name": "kubernetes-dashboard-5b5bf59977-t9xb9",
82. kubernetes-dashboard
84. Helm The package manager for Kubernetes
85. $ helm install stable/wordpress
86. Let's start deploying
87. We will use:
88. SysEleven MetaKube
89. We will all use the same cluster
90. Please create and then do everything in your own Namespace
91. Please create and then do everything in your own Namespace
92. Demo code and instructions: https:/ /github.com/bashofmann/ phpuk19-k8s-workshop
93. # 01 Deploying a simple Web Application
94. What did just happen?
96. Deployment created
97. Sees new Deployment And creates new ReplicaSet with 0 replicas
98. Scales new ReplicaSet up
99. Sees new ReplicaSet and Creates Pod for ReplicaSet
100. Sees new unscheduled Pod and Schedules it to Node
101. Sees it is supposed to start a Pod And starts its Containers
102. Service created
103. Sees the new Service And configures IP Table Rules and DNS entries
104. Sees the new Service has the Type LoadBalancer and creates An External LB at the Cloud Provider
105. How is traffic routed to the Pod
106. The Service loadbalances incoming traffic to all available Pods
107. Every Service has a virtual IP
108. Round Robin with IP Tables rules
109. OpenStack LoadBalancer
110. # 02 Using an Ingress with TLS
111. The ingress controller (nginx) listens on Ingress Resources and configures itself to route incoming traffic to the correct running pods
112. Cert-manager listens on Ingresses and if they want TLS, requests a certificate from LetsEncrypt
113. $ helm install stable/nginx-ingress $ kubectl apply -f https://raw.githubusercontent.com/ jetstack/cert-manager/release-0.6/deploy/manifests/00- crds.yaml $ helm install stable/cert-manager
114. How is traffic routed to the Pod
115. OpenStack LoadBalancer
116. # 03 Application Configuration
117. Configuration should not be part of a Docker Image
118. So that you can use the same Docker Image in multiple environments
119. Kubernetes comes with Key-Value Store Resources
120. ConfigMaps
121. Secrets
122. Can be mounted inside of containers
123. Environment Variables
124. Volumes
125. # 04 Helm Package Manager
126. Helm
128. Allows to install applications
129. So called "charts"
130. Writing your own charts if fairly easy
131. Charts can depend on other charts
132. Multiple deployments of one chart possible
133. Different namespaces
134. Different release names
135. Configuration over values
137. $ helm install stable/wordpress --namespace bastian --name my-wordpress --values dev.yaml --values bastian.yaml
138. # 05 Service Discovery
139. Kubernetes has an internal DNS for service discovery
140. Every Service has a DNS entry
141. service-name[.namespace]
142. # 06 Databases and Persistent Storage
143. You define a Persistent Volume or Storage Class, e.g. NFS, …
144. Depends on your Kubernetes Setup
145. Each pod can specify a Persistent Volume Claim
146. apiVersion: v1 kind: PersistentVolumeClaim metadata: name: postgresql-pv-claim labels: name: postgresql spec: storageClassName: generic accessModes: - ReadWriteOnce resources: requests: storage: 10Gi
147. And then mount the Claim into a Volume in a container
148. apiVersion: extensions/v1beta1 kind: Deployment metadata: name: postgresql spec: template: spec: containers: … volumes: - name: postgresql-data persistentVolumeClaim: claimName: postgresql-pv-claim
149. https:/ /kubernetes.io/docs/concepts/ storage/persistent-volumes/
150. # 07 Service Meshes
151. What are Service Meshes?
153. They provide
154. Metrics and Traces
155. Transparent End-To-End Encryption
156. Advanced Routing
157. Istio
158. LinkerD
159. $ linkerd install | kubectl apply -f -
160. # 08 Monitoring
161. Prometheus
162. $ helm install stable/prometheus
163. Automatically scrapes all Services/Pods with a Prometheus Scraping Annotation
164. # 09 Logging
165. Applications just log to stdout & stderr
166. Kubernetes writes logs of containers to the Node's Filesystem
167. Fluentd runs as a DaemonSet on every Node
168. Mounts the local Host Path of the Logs
169. Tails on Logs and enriches it with Meta Information
170. Sends it to ElasticSearch
171. Kibana as a nice Dashboard
172. $ helm install stable/elasticsearch $ helm install stable/fluentd-elasticsearch --set elasticsearch.host=elasticsearch- client,elasticsearch.port=9200 $ helm install stable/kibana # with some configuration
173. # 10 Debugging
174. Not all services have an ingress
175. Accessing Kubernetes from the outside
176. web quote-svc hello-svc
177. Getting a shell in a running container
178. $ kubectl exec $POD_NAME -i -t -- /bin/bash
179. Port forwarding through kubectl
180. $ kubectl port-forward pod/$POD_NAME 8080:80
181. $ kubectl port-forward service/$SERVICE_NAME 8080:80
182. Still, if you make a code change you have to commit, push, build, deploy
183. Takes some time
184. What about step debugging?
185. Of course you can run everything locally
186. But you develop only on one service
187. There may be lots of services
188. You don't want to expose all services publicly
189. Port-forwarding all services is also work
190. Telepresence
192. Creates a two-way proxy between the Kubernetes cluster and you
193. $ telepresence T: Starting proxy with method 'vpn-tcp'... @fhgbvx65xg|bash-3.2$ curl http://quote-svc/quote | jq '.' [ { "ID": 503, "title": "stefan sagmeister", "content": "<p>...</p>\n", "link": "https://quotesondesign.com/stefan- sagmeister-2/" } ]
194. Swap a running deployment in the cluster with a local process
195. ... or a locally running docker container
196. $ telepresence --swap-deployment quote-svc --namespace dev-flow-demo --expose 3000 --run npm run debug T: Starting proxy with method 'vpn-tcp',... T: Forwarding remote port 3000 to local port 3000.... > quote-svc@1.0.0 debug /Users/bhofmann/forge_test/quote- svc > nodemon --inspect quote-svc.js [nodemon] watching: *.* [nodemon] starting `node --inspect quote-svc.js` Debugger listening on ws://127.0.0.1:9229/83aa27ac- d879-4b50-a228-440354cca791 quote svc listening on port 3000!
197. # 11 (Auto) Scaling
198. Manual Scaling
199. kubectl scale --replicas=3 deployment/my-app
200. AutoScaling
201. Pods
202. Nodes
203. Summary
204. Powerful
205. Helpful
206. Better resource usage
207. Great tools because of standardized APIs
208. Fast paced development
209. Keep up to date
210. Documentation
211. https:/ /kubernetes.io/docs/
212. KubeCons
213. https:/ /www.youtube.com/channel/ UCvqbFHwN-nwalWPjPUKpvTA
214. http:/ /speakerdeck.com/ u/bastianhofmann
215. Please provide feedback
216. mail@bastianhofmann.de https:/ /twitter.com/BastianHofmann