Kubernetify All The Things

Kubernetes 101 talk for Pittsburgh Tech Fest 2017

Transcript

1. KUBERNETIFY ALL THE THINGS @STEVESLOKA PghTechFest 2017
2. OVERVIEW ▸ Overview ▸ Background of Kubernetes ▸ k8s concepts ▸ Demos ▸ Even More Demo ▸ Lulz throughout
3. SOFTWARE ARCHITECT ABOUT ME GOLANG / OPENSOURCE / KUBERNETES / CONTAINERS
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. KUBERNETES “HELMSMAN OF A SHIP” ▸ Managing distributed solutions at scale, based on years of industry expertise (Google-scale experience) ▸ High availability of the control plane and user workloads (when using pod replication), avoiding most single points of failure ▸ Modular control plane architecture, allowing many peices to be replaced without disrupting workload availability ▸ Persist all of it's internal platform state within an etcd database
7. COMMUNITY KUBERNETES
8. ARCHITECTURE Master: Node(s): ETCD API SERVER CONTROLLER MANAGER KUBELET PROXY SCHEDULER CONTAINER ENGINE CADVISOR SOFTWARE DEFINED NETWORK ADDONS
9. PAM WEBO2 DWIGHT DB01 JIM
10. APPLICATION CONTAINERS KUBERNETES CLUSTER OF MACHINES
11. HIGH LEVEL CONCEPTS ▸node ▸pod ▸scheduler ▸labels ▸deployments ▸services
12. ADVANCED ▸run a cluster ▸operators
13. NODE
14. NODE RESPONSIBILITIES 1.Runs containers ‣container engine (docker / rkt) ‣kubelet 2.Proxies service requests ‣kube-proxy
15. POD
16. PODS REPRESENTS A LOGICAL APPLICATION CONTAINER CONTAINER ‣Shared ‣namespaces ‣volumes
17. POD EXAMPLE: REST API (CONTAINER) LOGGER (CONTAINER) Logs
18. SCHEDULER
19. SCHEDULER ▸assign workloads to nodes ▸best fit chosen based on pod requirements ▸allows for over-commit ▸pluggable
20. LABELS
21. LABELS LABELS EXAMPLE: TYPE=FRONTEND
 ENV=PRODUCTION TYPE=FRONTEND
 ENV=STAGING TYPE=BACKEND
 ENV=PRODUCTION ENG=STEVE
 ENV=STAGING
22. LABELS TYPE=FRONTEND TYPE=FRONTEND
 ENV=PRODUCTION TYPE=FRONTEND
 ENV=STAGING TYPE=BACKEND
 ENV=PRODUCTION ENG=STEVE
 ENV=STAGING
23. LABELS ENV=PRODUCTION TYPE=BACKEND
 ENV=PRODUCTION ENG=STEVE
 ENV=STAGING TYPE=FRONTEND
 ENV=PRODUCTION TYPE=FRONTEND
 ENV=STAGING
24. LABELS ENG=STEVE TYPE=FRONTEND
 ENV=PRODUCTION TYPE=FRONTEND
 ENV=STAGING TYPE=BACKEND
 ENV=PRODUCTION ENG=STEVE
 ENV=STAGING
25. DESIRED STATE
26. DESIRED STATE
27. CREATE PODS Desired: Actual: POD POD POD POD POD POD ACTION IS TO CREATE 3 PODS ——>
28. DELETE PODS Desired: Actual: POD POD POD POD ACTION IS TO DELETE 2 PODS ——>
29. HEALTH CHECK Desired: Actual: POD POD POD POD ACTION IS TO CREATE 2 PODS ——> POD POD
31. DEPLOYMENTS
32. DEPLOYMENTS ▸Pod template ▸Docker image(s) ▸Labels ▸CPU / Memory ▸Replicas ▸Volume Mounts ▸Define in JSON || YAML
33. DEPLOYMENT EXAMPLE
34. VOLUMES ▸ emptyDir ▸ hostPath ▸ gcePersistentDisk ▸ awsElasticBlockStore ▸ nfs ▸ persistentVolumeClaim ▸ flocker ▸ glusterfs ▸ rbd ▸ gitRepo ▸ secret ▸ iscsi
35. SERVICES
36. 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.CLUSTER.LOCAL API.NAMESPACE.SVC.CLUSTER.LOCAL DB.NAMESPACE.SVC.CLUSTER.LOCAL
37. KUBERNETES PODS ARE MORTAL. THEY ARE BORN AND THEY DIE, AND THEY ARE NOT RESURRECTED.
38. SERVICES SERVICE DISCOVERY FOR PODS ▸proxy runs on each node ▸virtual IP per service ▸dns address ▸[serviceName] ▸[serviceName].[namespace] ▸[serviceName].[namespace].svc.cluster.local ▸dynamic “pods” based on label queries ▸pods are auto-injected with environment variables
40. SERVICES SERVICE TYPES ▸NodePort: Allocated port (range 30000-32767) ▸LoadBalancer: Provision loadbalancer on cloud provider ▸External IP’s
41. NAMESPACES
42. NAMESPACES 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.)
43. HEALTH CHECKS
44. HEALTH CHECKS READINESS PROBES ▸Am I ready to take requests? ▸Types: ▸Command ▸HTTP ▸TCP
45. HEALTH CHECKS LIVENESS PROBES ▸I was ready, am I still? ▸/healthz
47. RUNNING A CLUSTER
48. RUNNING A CLUSTER MINIKUBE ▸https://github.com/kubernetes/minikube ▸google kubeadm (1st link) ▸Google Container Engine (Kubernetes) KUBEADM GKE
49. RUNNING A CLUSTER UPMC ENTERPRISES ▸https://github.com/upmc-enterprises/ kubernetes-on-aws ▸CoreOS ▸NIST Standards ▸Bastion Hosts ▸Autoscaling
50. OPERATORS
51. OPERATORS THAT’S ME RIGHT? ▸“An Operator represents human operational knowledge in software to reliably manage an application.” 
 ~ CoreOS
52. OPERATORS EXAMPLES ▸etcd 
 (https://github.com/coreos/etcd-operator/) ▸Prometheus 
 (https://github.com/coreos/prometheus-operator) ▸Rook
 (https://github.com/rook/rook) ▸Elasticsearch
 (https://github.com/upmc-enterprises/elasticsearch-operator) ▸Kong
 (https://github.com/upmc-enterprises/kong-operator)
53. THANK YOU! @stevesloka github.com/stevesloka github.com/upmc-enterprises enterprises.upmc.com