2016 Zimowisko - Road to Kubernetes

Rough overview of Kubernetes and reasons we moved to it during 2016 "Zimowisko Linuxowe" in Puck

Transcript

1. Road to Kubernetes Radek “Goblin” Pieczonka <goblin@pentex.pl> Story of a certain infrastructure evolution
2. Who am I? - first “Hello World” in Basic on Timex 2048 (ZX Spectrum “clone”) in 1988, later C64, first x86 in 1995 - after short Red Hat adventure settled down with Slackware for years, later on migrating to Debian flavor - amateur local network started in 2000 that grew to local ISP business with ~300 households connected at peak capacity. Consolidated (aka sold) in 2009 - coming from operations, with some PHP experience in 2008 started to work as PM / TL / (Dev|Web|Whatever)Ops for couple of web projects / clients - recently joined Schibsted Tech Polska for NWT project - most notable clients recently: logic-immo.be & nwt.se
3. Project background Old infra, migration, JAVA monolith => modernize
4. Infrastructure ‘15 Docker, CoreOS, Etcd, Fleet, autodiscovery
5. What is NOT cool Selfmade - documentation & maintenance Bloated (aka fat) containers
6. Short story of Kubernetes Google, cgroups, BORG, Docker, Rkt 1.0 (Jun 2015)
7. Core K8S concepts Label, Annotation, Node, Pod, Volumes (PVs), Service, RC
8. apiVersion: v1 kind: ReplicationController metadata: name: kube-dns-v11 namespace: kube-system labels: k8s-app: kube-dns version: v11 kubernetes.io/cluster-service: "true" spec: replicas: 3 selector: k8s-app: kube-dns version: v11 template: metadata: labels: k8s-app: kube-dns version: v11 kubernetes.io/cluster-service: "true" spec: containers: - name: etcd image: gcr.io/google_containers/etcd-amd64 resources: limits: cpu: 100m memory: 500Mi requests: cpu: 100m memory: 50Mi command: - /usr/local/bin/etcd - -data-dir - /var/etcd/data - -listen-client-urls - http://127.0.0.1:2379,http://127.0.0.1:4001 - -advertise-client-urls - http://127.0.0.1:2379,http://127.0.0.1:4001 - -initial-cluster-token - skydns-etcd volumeMounts: - name: etcd-storage mountPath: /var/etcd/data
9. - name: kube2sky image: gcr.io/google_containers/kube2sky:1.14 resources: limits: cpu: 100m memory: 200Mi requests: cpu: 100m memory: 50Mi livenessProbe: httpGet: path: /healthz port: 8080 scheme: HTTP initialDelaySeconds: 60 timeoutSeconds: 5 successThreshold: 1 failureThreshold: 5 readinessProbe: httpGet: path: /readiness port: 8081 scheme: HTTP initialDelaySeconds: 30 timeoutSeconds: 5 args: - --domain=cluster.lan - name: skydns image: gcr.io/google_containers/skydns:201… resources: limits: cpu: 100m memory: 200Mi requests: cpu: 100m memory: 50Mi args: # command = "/skydns" - -machines=http://127.0.0.1:4001 - -addr=0.0.0.0:53 - -ns-rotate=false - -domain=cluster.lan ports: - containerPort: 53 name: dns protocol: UDP - containerPort: 53 name: dns-tcp protocol: TCP
10. - name: healthz image: gcr.io/google_containers/exechealthz:1.0 resources: limits: cpu: 10m memory: 20Mi requests: cpu: 10m memory: 20Mi args: - -cmd=nslookup kubernetes.default.svc.cluster.lan 127.0.0.1 >/dev/null - -port=8080 ports: - containerPort: 8080 protocol: TCP volumes: - name: etcd-storage emptyDir: {} dnsPolicy: Default # Don't use cluster DNS.
11. apiVersion: v1 kind: Service metadata: name: kube-dns namespace: kube-system labels: k8s-app: kube-dns kubernetes.io/cluster-service: "true" kubernetes.io/name: "KubeDNS" spec: selector: k8s-app: kube-dns clusterIP: 10.10.20.10 ports: - name: dns port: 53 protocol: UDP - name: dns-tcp port: 53 protocol: TCP
12. K8S cluster Master (API, sched, ctrl-mgr) Node (kubelet, proxy) AddOns (dns, monitoring, logging etc.)
13. Recent K8S improvements Deployments, HPA, DaemonSets, Jobs, Ingress, Ubernetes Lite
14. Road to Kubernetes Radek “Goblin” Pieczonka <goblin@pentex.pl>