Micro-datacenter chaos monkeys! Raspberry Pi & Kubernetes

Pittsburgh Tech Fest 2016

Transcript

1. MICRO-DATACENTER CHAOS MONKEYS! @STEVESLOKA PGHTECHFEST 2016
2. OVERVIEW ▸ Overview ▸ Background of Kubernetes ▸ k8s Concepts ▸ DEMO!!! (On a Pi cluster! —————————————————> ▸ Even More Demo ▸ More Demo ———————————————> ▸ Summary
3. SOFTWARE ARCHITECT ABOUT ME
4. KUBERNETES ▸ open-source platform for automating deployment, scaling, and operations of application containers ▸ Servers 2-N ▸ Open Sourced by Google 2014 ▸ github.com/kubernetes/kubernetes ▸ Written in Go ▸ #GIFEE (Google-like Infrastructure for Everyone Else)
5. GOOGLE EXPERIENCE ‣ Google has been using containers for over a decade ‣ 2 BILLON Per Week! (With a “B”) ‣ Everything at Google runs in a container
6. “HELMSMAN OF A SHIP” ▸ lean: lightweight, simple, accessible ▸ extensible: modular, pluggable, hookable, composable, toolable ▸ portable: public, private, hybrid, multi cloud ▸ self-healing: auto-placement, auto-restart, auto- replication
7. COMMUNITY KUBERNETES
8. PAM WEBO2 DWIGHT DB01
9. APPLICATION CONTAINERS KUBERNETES CLUSTER OF MACHINES
10. HIGH LEVEL CONCEPTS ▸node ▸pod ▸scheduler ▸labels ▸deployments / replica set ▸services
11. ARCHITECTURE Master(s): Node(s): ETCD API SERVER CONTROLLER MANAGER KUBELET PROXY SCHEDULER CONTAINER ENGINE CADVISOR SOFTWARE DEFINED NETWORK ADDONS
12. NODE
13. NODE RESPONSIBILITIES 1.Runs containers ‣container engine (docker / rkt) ‣kubelet 2.Proxies service requests ‣kubeproxy
14. POD
15. REPRESENTS A LOGICAL APPLICATION CONTAINER CONTAINER ‣Shared ‣namespaces ‣volumes
16. POD EXAMPLE: REST API (CONTAINER) LOGGER (CONTAINER) Logs
17. SCHEDULER
18. SCHEDULES PODS TO RUN ON NODES ▸global ▸best fit chosen based on pod requirements ▸allows for over-commit ▸pluggable
19. LABELS
20. LABELS EXAMPLE: TYPE=FRONTEND
 ENV=PRODUCTION TYPE=FRONTEND
 ENV=STAGING TYPE=BACKEND
 ENV=PRODUCTION ENG=STEVE
 ENV=STAGING
21. TYPE=FRONTEND TYPE=FRONTEND
 ENV=PRODUCTION TYPE=FRONTEND
 ENV=STAGING TYPE=BACKEND
 ENV=PRODUCTION ENG=STEVE
 ENV=STAGING
22. ENV=PRODUCTION TYPE=BACKEND
 ENV=PRODUCTION ENG=STEVE
 ENV=STAGING TYPE=FRONTEND
 ENV=PRODUCTION TYPE=FRONTEND
 ENV=STAGING
23. ENG=STEVE TYPE=FRONTEND
 ENV=PRODUCTION TYPE=FRONTEND
 ENV=STAGING TYPE=BACKEND
 ENV=PRODUCTION ENG=STEVE
 ENV=STAGING
24. DESIRED STATE
26. CREATE PODS Desired: Actual: POD POD POD POD POD POD ACTION IS TO CREATE 3 PODS ——>
27. DELETE PODS Desired: Actual: POD POD POD POD ACTION IS TO DELETE 2 PODS ——>
28. HEALTH CHECK Desired: Actual: POD POD POD POD ACTION IS TO CREATE 2 PODS ——> POD POD
30. DEPLOYMENTS / REPLICA SETS
31. DEPLOYMENTS ▸Pod template ▸Docker image(s) ▸Labels ▸CPU / Memory ▸Replicas ▸Volume Mounts ▸Revisions ▸Strategy ▸Define in JSON || YAML
32. DEPLOYMENT EXAMPLE
33. DEPLOYMENTS VOLUMES ▸ emptyDir ▸ hostPath ▸ gcePersistentDisk ▸ awsElasticBlockStore ▸ nfs ▸ persistentVolumeCla im ▸ flocker ▸ glusterfs ▸ rbd ▸ gitRepo ▸ secret ▸ iscsi
34. SERVICES
35. KUBERNETES SAMPLE NGINX NGINX LOAD BALANCER API API API API LOAD BALANCER NGINX DB LOAD BALANCER K8S SERVICE K8S SERVICE K8S SERVICE NGINX.NAMESPACE.SVC.K8S.LOCAL API.NAMESPACE.SVC.K8S.LOCAL DB.NAMESPACE.SVC.K8S.LOCAL
36. KUBERNETES PODS ARE MORTAL. THEY ARE BORN AND THEY DIE, AND THEY ARE NOT RESURRECTED.
37. SERVICE DISCOVERY FOR PODS ▸proxy runs on each node ▸virtual IP per service ▸dns address ▸[serviceName].[namespace].svc.k8s.local ▸dynamic “pods” based on label queries ▸pods are auto-injected with environment variables
40. SERVICE TYPES ▸ClusterIP: Internal to the cluster (SDN) ▸NodePort: Allocated port (range 30000-32767) ▸LoadBalancer: Provision loadbalancer on cloud provider
41. NAMESPACES
42. PARTITION RESOURCES ▸A mechanism to partition resources created by users into a logically named group ▸Allows for work to be done in isolation ▸Each namespace is given its own: 1.resources (pods, services, replication controllers, etc.) 2.policies (who can or cannot perform actions in their namespace) 3.constraints (this namespace is allowed this much quota, etc.)
44. THANK YOU! @stevesloka steve@stevesloka.com github.com/stevesloka github.com/upmc-enterprises enterprises.upmc.com