|
Size: 39731
Comment:
|
← Revision 90 as of 2024-10-26 09:41:38 ⇥
Size: 30818
Comment:
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 2: | Line 2: |
| <<TableOfContents(2)>> | |
| Line 9: | Line 10: |
| $ minikube version minikube version: v1.2.0 $ minikube start * minikube v1.2.0 on linux (amd64) * Creating none VM (CPUs=2, Memory=2048MB, Disk=20000MB) ... * Configuring environment for Kubernetes v1.15.0 on Docker 18.09.5 - kubelet.resolv-conf=/run/systemd/resolve/resolv.conf * Pulling images ... * Launching Kubernetes ... * Configuring local host environment ... * Verifying: apiserver proxy etcd scheduler controller dns * Done! kubectl is now configured to use "minikube" |
minikube version # minikube version: v1.2.0 minikube start # * minikube v1.2.0 on linux (amd64) # * Creating none VM (CPUs=2, Memory=2048MB, Disk=20000MB) ... # * Configuring environment for Kubernetes v1.15.0 on Docker 18.09.5 # - kubelet.resolv-conf=/run/systemd/resolve/resolv.conf # * Pulling images ... # * Launching Kubernetes ... # # * Configuring local host environment ... # * Verifying: apiserver proxy etcd scheduler controller dns # * Done! kubectl is now configured to use "minikube" |
| Line 26: | Line 27: |
| $ kubectl cluster-info Kubernetes master is running at https://172.17.0.30:8443 KubeDNS is running at https://172.17.0.30:8443/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'. |
kubectl cluster-info # Kubernetes master is running at https://172.17.0.30:8443 # KubeDNS is running at https://172.17.0.30:8443/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy # # To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'. |
| Line 35: | Line 36: |
| $ kubectl get nodes NAME STATUS ROLES AGE VERSION minikube Ready master 3m1s v1.15.0 }}} == deploy containers == |
kubectl get nodes # NAME STATUS ROLES AGE VERSION # minikube Ready master 3m1s v1.15.0 }}} == Deploy containers == |
| Line 43: | Line 44: |
| $ kubectl create deployment first-deployment --image=katacoda/docker-http-server deployment.apps/first-deployment created $ # deploy container in cluster |
kubectl create deployment first-deployment --image=katacoda/docker-http-server # deployment.apps/first-deployment created # deploy container in cluster |
| Line 47: | Line 48: |
| $ kubectl get pods NAME READY STATUS RESTARTS AGE first-deployment-8cbf74484-s2fkl 1/1 Running 0 25s |
kubectl get pods # NAME READY STATUS RESTARTS AGE # first-deployment-8cbf74484-s2fkl 1/1 Running 0 25s |
| Line 51: | Line 52: |
| $ kubectl expose deployment first-deployment --port=80 --type=NodePort service/first-deployment exposed $ kubectl get svc first-deployment NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE first-deployment NodePort 10.98.246.87 <none> 80:31219/TCP 105s |
kubectl expose deployment first-deployment --port=80 --type=NodePort # service/first-deployment exposed kubectl get svc first-deployment # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE # first-deployment NodePort 10.98.246.87 <none> 80:31219/TCP 105s |
| Line 58: | Line 59: |
| $ curl 10.98.246.87:80 <h1>This request was processed by host: first-deployment-8cbf74484-s2fkl</h1> $curl host01:31219 <h1>This request was processed by host: first-deployment-8cbf74484-s2fkl</h1> |
curl 10.98.246.87:80 # <h1>This request was processed by host: first-deployment-8cbf74484-s2fkl</h1> # curl host01:31219 # <h1>This request was processed by host: first-deployment-8cbf74484-s2fkl</h1> |
| Line 68: | Line 69: |
| $ minikube addons enable dashboard | minikube addons enable dashboard |
| Line 70: | Line 71: |
| in a UI. * dashboard was successfully enabled $ kubectl apply -f /opt/kubernetes-dashboard.yaml |
# in a UI. # * dashboard was successfully enabled kubectl apply -f /opt/kubernetes-dashboard.yaml |
| Line 74: | Line 75: |
| service/kubernetes-dashboard-katacoda created |
# service/kubernetes-dashboard-katacoda created |
| Line 77: | Line 77: |
| $ kubectl get pods -n kube-system -w #check progress NAME READY STATUS RESTARTS AGE coredns-5c98db65d4-b2kxm 1/1 Running 0 17m coredns-5c98db65d4-mm567 1/1 Running 1 17m etcd-minikube 1/1 Running 0 16m kube-addon-manager-minikube 1/1 Running 0 16m kube-apiserver-minikube 1/1 Running 0 16m kube-controller-manager-minikube 1/1 Running 0 16m kube-proxy-pngm9 1/1 Running 0 17m kube-scheduler-minikube 1/1 Running 0 16m kubernetes-dashboard-7b8ddcb5d6-xt5nt 1/1 Running 0 76s storage-provisioner 1/1 Running 0 17m ^C$ |
kubectl get pods -n kube-system -w #check progress # NAME READY STATUS RESTARTS AGE # coredns-5c98db65d4-b2kxm 1/1 Running 0 17m # coredns-5c98db65d4-mm567 1/1 Running 1 17m # etcd-minikube 1/1 Running 0 16m # kube-addon-manager-minikube 1/1 Running 0 16m # kube-apiserver-minikube 1/1 Running 0 16m # kube-controller-manager-minikube 1/1 Running 0 16m # kube-proxy-pngm9 1/1 Running 0 17m # kube-scheduler-minikube 1/1 Running 0 16m # kubernetes-dashboard-7b8ddcb5d6-xt5nt 1/1 Running 0 76s # storage-provisioner 1/1 Running 0 17m |
| Line 167: | Line 166: |
| master $ mkdir -p $HOME/.kube master $ pwd /root master $ sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config master $ sudo chown $(id -u):$(id -g) $HOME/.kube/config master $ export KUBECONFIG=$HOME/.kube/config master $ echo $KUBECONFIG/root/.kube/config }}} == deploy cni weaveworks - deploy a pod network to the cluster == |
# In master mkdir -p $HOME/.kube pwd # /root sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config sudo chown $(id -u):$(id -g) $HOME/.kube/config export KUBECONFIG=$HOME/.kube/config echo $KUBECONFIG/root/.kube/config }}} == Deploy cni weaveworks - deploy a pod network to the cluster == |
| Line 181: | Line 181: |
| master $ kubectl apply -f /opt/weave-kube serviceaccount/weave-net created clusterrole.rbac.authorization.k8s.io/weave-net created clusterrolebinding.rbac.authorization.k8s.io/weave-net created role.rbac.authorization.k8s.io/weave-net created rolebinding.rbac.authorization.k8s.io/weave-net created daemonset.extensions/weave-net created master $ kubectl get pod -n kube-system NAME READY STATUS RESTARTS AGE coredns-fb8b8dccf-b9rd7 1/1 Running 0 11m coredns-fb8b8dccf-sfgbn 1/1 Running 0 11m etcd-master 1/1 Running 0 10m kube-apiserver-master 1/1 Running 0 10m kube-controller-manager-master 1/1 Running 0 10m kube-proxy-l42wp 1/1 Running 0 11m kube-scheduler-master 1/1 Running 1 10m weave-net-mcxml 2/2 Running 0 84s }}} == join cluster == {{{#!highlight bash master $ kubeadm token list # check tokens TOKEN TTL EXPIRES USAGES DESCRIPTION EXTRA GROUPS xfvno5.q2xfb2m3nw7grdjm 23h 2019-07-28T16:19:18Z authentication,signing The default bootstrap token generated b y 'kubeadm init'. system:bootstrappers:kubeadm:default-node-token |
# In master kubectl apply -f /opt/weave-kube # serviceaccount/weave-net created # clusterrole.rbac.authorization.k8s.io/weave-net created # clusterrolebinding.rbac.authorization.k8s.io/weave-net created # role.rbac.authorization.k8s.io/weave-net created # rolebinding.rbac.authorization.k8s.io/weave-net created # daemonset.extensions/weave-net created kubectl get pod -n kube-system # NAME READY STATUS RESTARTS AGE # coredns-fb8b8dccf-b9rd7 1/1 Running 0 11m # coredns-fb8b8dccf-sfgbn 1/1 Running 0 11m # etcd-master 1/1 Running 0 10m # kube-apiserver-master 1/1 Running 0 10m # kube-controller-manager-master 1/1 Running 0 10m # kube-proxy-l42wp 1/1 Running 0 11m # kube-scheduler-master 1/1 Running 1 10m # weave-net-mcxml 2/2 Running 0 84s }}} == Join cluster == {{{#!highlight bash # In master kubeadm token list # check tokens # TOKEN TTL EXPIRES USAGES DESCRIPTION # EXTRA GROUPS # xfvno5.q2xfb2m3nw7grdjm 23h 2019-07-28T16:19:18Z authentication,signing The default bootstrap # token generated by 'kubeadm init'. system:bootstrappers:kubeadm:default-node-token |
| Line 214: | Line 214: |
| [preflight] Running pre-flight checks [preflight] Reading configuration from the cluster... [preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -oyaml' [kubelet-start] Downloading configuration for the kubelet from the "kubelet-config-1.14" ConfigMap in the kube-system namespace [kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml" [kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env" [kubelet-start] Activating the kubelet service [kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap... This node has joined the cluster: * Certificate signing request was sent to apiserver and a response was received. * The Kubelet was informed of the new secure connection details. Run 'kubectl get nodes' on the control-plane to see this node join the cluster. |
# [preflight] Running pre-flight checks # [preflight] Reading configuration from the cluster... # [preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -oyaml' # [kubelet-start] Downloading configuration for the kubelet from the "kubelet-config-1.14" ConfigMap in the kube-system namespace # [kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml" # [kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env" # [kubelet-start] Activating the kubelet service # [kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap... # # This node has joined the cluster: # * Certificate signing request was sent to apiserver and a response was received. # * The Kubelet was informed of the new secure connection details. # # Run 'kubectl get nodes' on the control-plane to see this node join the cluster. |
| Line 231: | Line 231: |
| master $ kubectl get nodes NAME STATUS ROLES AGE VERSION master Ready master 17m v1.14.0 node01 Ready <none> 107s v1.14.0 bootstrap token generated b master $ |
kubectl get nodes # NAME STATUS ROLES AGE VERSION # master Ready master 17m v1.14.0 # node01 Ready <none> 107s v1.14.0 # bootstrap token generated b |
| Line 238: | Line 238: |
| node01 $ kubectl get nodesThe connection to the server localhost:8080 was refused - did you specify the right host or port ? node01 $ }}} == deploy container in cluster == {{{#!highlight bash master $ kubectl create deployment http --image=katacoda/docker-http-server:latest deployment.apps/http created master $ kubectl get pods NAME READY STATUS RESTARTS AGE http-7f8cbdf584-74pd9 1/1 Running 0 11s master $ docker ps | grep http-server master $ node01 $ docker ps | grep http-serveradb3cde7f861 katacoda/docker-http-server "/app" About a minute ago Up About a minute k8s_docker-http-server_http-7f8cbdf584-74pd9_default_04a 17065-b08d-11e9-bff1-0242ac110045_0 # expose deployment master $ kubectl get pods NAME READY STATUS RESTARTS AGE http-7f8cbdf584-74pd9 1/1 Running 0 17m bootstrap token generated b master $ kubectl expose deployment http --port=80 --type=NodePort service/http exposed master $ kubectl get service http NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE http NodePort 10.101.65.149 <none> 80:30982/TCP 49s master $ curl 10.101.65.149:80 <h1>This request was processed by host: http-7f8cbdf584-74pd9</h1> master $ curl http://10.101.65.149 <h1>This request was processed by host: http-7f8cbdf584-74pd9</h1> }}} == apply dashboard in cluster == |
kubectl get nodes # The connection to the server localhost:8080 was refused - did you specify the right host or port }}} == Deploy container in cluster == {{{#!highlight bash # In master kubectl create deployment http --image=katacoda/docker-http-server:latest # deployment.apps/http created kubectl get pods # NAME READY STATUS RESTARTS AGE # http-7f8cbdf584-74pd9 1/1 Running 0 11s docker ps | grep http-server # In node01 docker ps | grep http-serveradb3cde7f861 # katacoda/docker-http-server "/app" # About a minute ago # Up About a minute k8s_docker-http-server_http-7f8cbdf584-74pd9_default_04a # 17065-b08d-11e9-bff1-0242ac110045_0 # expose deployment in master kubectl get pods # NAME READY STATUS RESTARTS AGE # http-7f8cbdf584-74pd9 1/1 Running 0 17m bootstrap # token generated b kubectl expose deployment http --port=80 --type=NodePort # service/http exposed kubectl get service http # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE # http NodePort 10.101.65.149 <none> 80:30982/TCP 49s curl 10.101.65.149:80 # <h1>This request was processed by host: http-7f8cbdf584-74pd9</h1> curl http://10.101.65.149 # <h1>This request was processed by host: http-7f8cbdf584-74pd9</h1> }}} == Apply dashboard in cluster == |
| Line 278: | Line 279: |
| {{{ master $ kubectl apply -f dashboard.yaml secret/kubernetes-dashboard-certs created serviceaccount/kubernetes-dashboard created role.rbac.authorization.k8s.io/kubernetes-dashboard-minimal created rolebinding.rbac.authorization.k8s.io/kubernetes-dashboard-minimal created deployment.apps/kubernetes-dashboard created service/kubernetes-dashboard created master $ kubectl get pods -n kube-system NAME READY STATUS RESTARTS AGEcoredns-fb8b8dccf-b9rd7 1/1 Running 0 42mcoredns-fb8b8dccf-sfgbn 1/1 Running 0 42m etcd-master 1/1 Running 0 41m kube-apiserver-master 1/1 Running 0 40m kube-controller-manager-master 1/1 Running 0 40m kube-proxy-gwrps 1/1 Running 0 26m kube-proxy-l42wp 1/1 Running 0 42m kube-scheduler-master 1/1 Running 1 40m kubernetes-dashboard-5f57845f9d-ls7q2 0/1 ContainerCreating 0 2s weave-net-gww8b 2/2 Running 0 26m weave-net-mcxml 2/2 Running 0 31m }}} Create service accoun for dashboard {{{ |
{{{#!highlight sh # In master kubectl apply -f dashboard.yaml # secret/kubernetes-dashboard-certs created # serviceaccount/kubernetes-dashboard created # role.rbac.authorization.k8s.io/kubernetes-dashboard-minimal created # rolebinding.rbac.authorization.k8s.io/kubernetes-dashboard-minimal created # deployment.apps/kubernetes-dashboard created # service/kubernetes-dashboard created kubectl get pods -n kube-system # NAME READY STATUS RESTARTS AGEcoredns-fb8b8dccf-b9rd7 # 1/1 Running 0 42mcoredns-fb8b8dccf-sfgbn 1/1 Running # 0 42m # etcd-master 1/1 Running 0 41m # kube-apiserver-master 1/1 Running 0 40m # kube-controller-manager-master 1/1 Running 0 40m # kube-proxy-gwrps 1/1 Running 0 26m # kube-proxy-l42wp 1/1 Running 0 42m # kube-scheduler-master 1/1 Running 1 40m # kubernetes-dashboard-5f57845f9d-ls7q2 0/1 ContainerCreating 0 2s # weave-net-gww8b 2/2 Running 0 26m # weave-net-mcxml 2/2 Running 0 31m }}} Create service account for dashboard {{{#!highlight yaml |
| Line 335: | Line 337: |
| == services == {{{#!highlight bash master $ kubectl get service NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE http NodePort 10.101.65.149 <none> 80:30982/TCP 17m kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 56m |
== List services == {{{#!highlight bash # In master kubectl get service # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE # http NodePort 10.101.65.149 <none> 80:30982/TCP 17m # kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 56m |
| Line 346: | Line 349: |
| * minikube v1.2.0 on linux (amd64) * Creating none VM (CPUs=2, Memory=2048MB, Disk=20000MB) ... * Configuring environment for Kubernetes v1.15.0 on Docker 18.09.5 - kubelet.resolv-conf=/run/systemd/resolve/resolv.conf * Pulling images ... * Launching Kubernetes ... * Configuring local host environment ... * Verifying: apiserver proxy etcd scheduler controller dns * Done! kubectl is now configured to use "minikube" $ kubectl get nodes NAME STATUS ROLES AGE VERSION minikube Ready master 2m2s v1.15.0 $ kubectl get service NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 2m18s |
# * minikube v1.2.0 on linux (amd64) # * Creating none VM (CPUs=2, Memory=2048MB, Disk=20000MB) ... # * Configuring environment for Kubernetes v1.15.0 on Docker 18.09.5 # - kubelet.resolv-conf=/run/systemd/resolve/resolv.conf # * Pulling images ... # * Launching Kubernetes ... # * Configuring local host environment ... # * Verifying: apiserver proxy etcd # # scheduler controller dns # * Done! kubectl is now configured to use "minikube" kubectl get nodes # NAME STATUS ROLES AGE VERSION # minikube Ready master 2m2s v1.15.0 kubectl get service # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE # kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 2m18s |
| Line 367: | Line 369: |
| Line 369: | Line 370: |
| $ kubectl run http --image=katacoda/docker-http-server:latest --replicas=1 kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version.Use kubectl run --generator=run-pod/v1 or kubectl create instead. deployment.apps/http created $ kubectl get deployments NAME READY UP-TO-DATE AVAILABLE AGE http 1/1 1 1 6s |
kubectl run http --image=katacoda/docker-http-server:latest --replicas=1 # kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version.Use kubectl run --generator=run-pod/v1 or kubectl create instead. # deployment.apps/http created kubectl get deployments # NAME READY UP-TO-DATE AVAILABLE AGE # http 1/1 1 1 6s |
| Line 380: | Line 381: |
| $ kubectl expose deployment http --external-ip="172.17.0.13" --port=8000 --target-port=80 service/http exposed $ curl http://172.17.0.13:8000 <h1>This request was processed by host: http-5fcf9dd9cb-zfkkz</h1> $ kubectl get pods NAME READY STATUS RESTARTS AGE http-5fcf9dd9cb-zfkkz 1/1 Running 0 3m26s $ kubectl get service NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE http ClusterIP 10.100.157.159 172.17.0.13 8000/TCP 57s kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 7m41s $ curl http://10.100.157.159:8000 <h1>This request was processed by host: http-5fcf9dd9cb-zfkkz</h1> $ kubectl run httpexposed --image=katacoda/docker-http-server:latest --replicas=1 --port=80 --host |
kubectl expose deployment http --external-ip="172.17.0.13" --port=8000 --target-port=80 # service/http exposed curl http://172.17.0.13:8000 # <h1>This request was processed by host: http-5fcf9dd9cb-zfkkz</h1> kubectl get pods # NAME READY STATUS RESTARTS AGE # http-5fcf9dd9cb-zfkkz 1/1 Running 0 3m26s kubectl get service # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE # http ClusterIP 10.100.157.159 172.17.0.13 8000/TCP 57s # kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 7m41s curl http://10.100.157.159:8000 # <h1>This request was processed by host: http-5fcf9dd9cb-zfkkz</h1> kubectl run httpexposed --image=katacoda/docker-http-server:latest --replicas=1 --port=80 --host |
| Line 400: | Line 401: |
| kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. Use kubectl run --generator=run-pod/v1 or kubectl create instead. deployment.apps/httpexposed created $ curl http://172.17.0.13:8001 <h1>This request was processed by host: httpexposed-569df5d86-rzzhb</h1> $ kubectl get svc NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE http ClusterIP 10.100.157.159 172.17.0.13 8000/TCP 3m50s kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 10m $ kubectl get pods NAME READY STATUS RESTARTS AGE http-5fcf9dd9cb-zfkkz 1/1 Running 0 7m9s httpexposed-569df5d86-rzzhb 1/1 Running 0 36s |
# kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version. # Use kubectl run --generator=run-pod/v1 or kubectl create instead. # deployment.apps/httpexposed created curl http://172.17.0.13:8001 # <h1>This request was processed by host: httpexposed-569df5d86-rzzhb</h1> kubectl get svc # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE # http ClusterIP 10.100.157.159 172.17.0.13 8000/TCP 3m50s # kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 10m kubectl get pods # NAME READY STATUS RESTARTS AGE # http-5fcf9dd9cb-zfkkz 1/1 Running 0 7m9s # httpexposed-569df5d86-rzzhb 1/1 Running 0 36s |
| Line 416: | Line 417: |
| $ kubectl scale --replicas=3 deployment http deployment.extensions/http scaled $ kubectl get pods # amount of pods for service http increased to 3 NAME READY STATUS RESTARTS AGE http-5fcf9dd9cb-fhljh 1/1 Running 0 31s http-5fcf9dd9cb-wb2dh 1/1 Running 0 31s http-5fcf9dd9cb-zfkkz 1/1 Running 0 9m27s httpexposed-569df5d86-rzzhb 1/1 Running 0 2m54s |
kubectl scale --replicas=3 deployment http # deployment.extensions/http scaled kubectl get pods # amount of pods for service http increased to 3 # NAME READY STATUS RESTARTS AGE # http-5fcf9dd9cb-fhljh 1/1 Running 0 31s # http-5fcf9dd9cb-wb2dh 1/1 Running 0 31s # http-5fcf9dd9cb-zfkkz 1/1 Running 0 9m27s # httpexposed-569df5d86-rzzhb 1/1 Running 0 2m54s |
| Line 427: | Line 428: |
$ kubectl get service NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE http ClusterIP 10.100.157.159 172.17.0.13 8000/TCP 7m28s kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 14m $ kubectl describe svc http Name: http Namespace: defaultLabels: run=httpAnnotations: <none> Selector: run=httpType: ClusterIPIP: 10.100.157.159 External IPs: 172.17.0.13 Port: <unset> 8000/TCP TargetPort: 80/TCP Endpoints: 172.18.0.4:80,172.18.0.6:80,172.18.0.7:80 Session Affinity: None Events: <none> $ curl http://172.17.0.13:8000 <h1>This request was processed by host: http-5fcf9dd9cb-wb2dh</h1> $ curl http://172.17.0.13:8000 <h1>This request was processed by host: http-5fcf9dd9cb-fhljh</h1> $ curl http://172.17.0.13:8000 <h1>This request was processed by host: http-5fcf9dd9cb-zfkkz</h1> |
kubectl get service # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE # http ClusterIP 10.100.157.159 172.17.0.13 8000/TCP 7m28s # kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 14m kubectl describe svc http # Name: http # Namespace: defaultLabels: run=httpAnnotations: <none> # Selector: run=httpType: ClusterIPIP: 10.100.157.159 # External IPs: 172.17.0.13 # Port: <unset> 8000/TCP # TargetPort: 80/TCP # Endpoints: 172.18.0.4:80,172.18.0.6:80,172.18.0.7:80 # Session Affinity: None # Events: <none> curl http://172.17.0.13:8000 # <h1>This request was processed by host: http-5fcf9dd9cb-wb2dh</h1> curl http://172.17.0.13:8000 # <h1>This request was processed by host: http-5fcf9dd9cb-fhljh</h1> curl http://172.17.0.13:8000 # <h1>This request was processed by host: http-5fcf9dd9cb-zfkkz</h1> |
| Line 455: | Line 455: |
| master $ launch.sh Waiting for Kubernetes to start... Kubernetes started master $ kubectl get nodes NAME STATUS ROLES AGE VERSION master Ready master 85m v1.14.0 node01 Ready <none> 85m v1.14.0 |
# In master launch.sh # Waiting for Kubernetes to start... # Kubernetes started kubectl get nodes # NAME STATUS ROLES AGE VERSION # master Ready master 85m v1.14.0 # node01 Ready <none> 85m v1.14.0 |
| Line 464: | Line 465: |
| master $ kubectl create deployment examplehttpapp --image=katacoda/docker-http-server deployment.apps/examplehttpapp created |
kubectl create deployment examplehttpapp --image=katacoda/docker-http-server # deployment.apps/examplehttpapp created |
| Line 469: | Line 470: |
| NAME READY UP-TO-DATE AVAILABLE AGE examplehttpapp 1/1 1 1 25s |
# NAME READY UP-TO-DATE AVAILABLE AGE # examplehttpapp 1/1 1 1 25s |
| Line 474: | Line 475: |
| NAME READY STATUS RESTARTS AGE examplehttpapp-58f66848-n7wn7 1/1 Running 0 71s |
# NAME READY STATUS RESTARTS AGE # examplehttpapp-58f66848-n7wn7 1/1 Running 0 71s |
| Line 478: | Line 479: |
| master $ kubectl get pods -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES examplehttpapp-58f66848-n7wn7 1/1 Running 0 113s 10.44.0.2 node01 <none> <none> |
kubectl get pods -o wide # NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE # READINESS GATES # examplehttpapp-58f66848-n7wn7 1/1 Running 0 113s 10.44.0.2 node01 <none> <none> |
| Line 483: | Line 484: |
| master $ kubectl describe pod examplehttpapp-58f66848-n7wn7 Name: examplehttpapp-58f66848-n7wn7 Namespace: default Priority: 0 PriorityClassName: <none> Node: node01/172.17.0.24 Start Time: Sat, 27 Jul 2019 17:59:35 +0000 Labels: app=examplehttpapp pod-template-hash=58f66848 Annotations: <none> Status: Running IP: 10.44.0.2 |
kubectl describe pod examplehttpapp-58f66848-n7wn7 # Name: examplehttpapp-58f66848-n7wn7 # Namespace: default # Priority: 0 # PriorityClassName: <none> # Node: node01/172.17.0.24 # Start Time: Sat, 27 Jul 2019 17:59:35 +0000 # Labels: app=examplehttpapp # pod-template-hash=58f66848 # Annotations: <none> # Status: Running # IP: 10.44.0.2 |
| Line 503: | Line 504: |
| master $ kubectl create ns testns namespace/testns created master $ kubectl create deployment namespacedeg -n testns --image=katacoda/docker-http-server deployment.apps/namespacedeg created master $ kubectl get pods -n testns NAME READY STATUS RESTARTS AGE namespacedeg-74dcc7dc64-wcxnj 1/1 Running 0 3s master $ kubectl get pods -n testns -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES namespacedeg-74dcc7dc64-wcxnj 1/1 Running 0 18s 10.44.0.3 node01 <none> <none> |
kubectl create ns testns # namespace/testns created kubectl create deployment namespacedeg -n testns --image=katacoda/docker-http-server # deployment.apps/namespacedeg created kubectl get pods -n testns # NAME READY STATUS RESTARTS AGE # namespacedeg-74dcc7dc64-wcxnj 1/1 Running 0 3s kubectl get pods -n testns -o wide # NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES # namespacedeg-74dcc7dc64-wcxnj 1/1 Running 0 18s 10.44.0.3 node01 <none> <none> |
| Line 515: | Line 516: |
| master $ kubectl scale deployment examplehttpapp --replicas=5 deployment.extensions/examplehttpapp scaled master $ kubectl get deployments -o wide NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR examplehttpapp 5/5 5 5 9m6s docker-http-server katacoda/docker-http-server app=examplehttpapp master $ kubectl get pods -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES examplehttpapp-58f66848-cf6pl 1/1 Running 0 65s 10.44.0.6 node01 <none> <none> examplehttpapp-58f66848-lfrq4 1/1 Running 0 65s 10.44.0.5 node01 <none> <none> examplehttpapp-58f66848-n7wn7 1/1 Running 0 9m26s 10.44.0.2 node01 <none> <none> examplehttpapp-58f66848-snwl7 1/1 Running 0 65s 10.44.0.7 node01 <none> <none> examplehttpapp-58f66848-vd8db 1/1 Running 0 65s 10.44.0.4 node01 <none> <none> |
kubectl scale deployment examplehttpapp --replicas=5 # deployment.extensions/examplehttpapp scaled kubectl get deployments -o wide # NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR # examplehttpapp 5/5 5 5 9m6s docker-http-server katacoda/docker-http-server app=examplehttpapp kubectl get pods -o wide # NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES # examplehttpapp-58f66848-cf6pl 1/1 Running 0 65s 10.44.0.6 node01 <none> <none> # examplehttpapp-58f66848-lfrq4 1/1 Running 0 65s 10.44.0.5 node01 <none> <none> # examplehttpapp-58f66848-n7wn7 1/1 Running 0 9m26s 10.44.0.2 node01 <none> <none> # examplehttpapp-58f66848-snwl7 1/1 Running 0 65s 10.44.0.7 node01 <none> <none> # examplehttpapp-58f66848-vd8db 1/1 Running 0 65s 10.44.0.4 node01 <none> <none> |
| Line 531: | Line 532: |
| master $ kubectl get nodes -o wide NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME master Ready master 102m v1.14.0 172.17.0.19 <none> Ubuntu 16.04.6 LTS 4.4.0-150-generic docker://18.9.5 node01 Ready <none> 102m v1.14.0 172.17.0.24 <none> Ubuntu 16.04.6 LTS 4.4.0-150-generic docker://18.9.5 |
kubectl get nodes -o wide # NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME # master Ready master 102m v1.14.0 172.17.0.19 <none> Ubuntu 16.04.6 LTS 4.4.0-150-generic docker://18.9.5 # node01 Ready <none> 102m v1.14.0 172.17.0.24 <none> Ubuntu 16.04.6 LTS 4.4.0-150-generic docker://18.9.5 |
| Line 538: | Line 539: |
| master $ kubectl --record=true set image deployment examplehttpapp docker-http-server=katacoda/docker-http-server:v2 deployment.extensions/examplehttpapp image updated master $ kubectl rollout status deployment examplehttpapp Waiting for deployment "examplehttpapp" rollout to finish: 1 out of 3 new replicas have been updated... Waiting for deployment "examplehttpapp" rollout to finish: 1 out of 3 new replicas have been updated... Waiting for deployment "examplehttpapp" rollout to finish: 1 out of 3 new replicas have been updated... Waiting for deployment "examplehttpapp" rollout to finish: 2 out of 3 new replicas have been updated... Waiting for deployment "examplehttpapp" rollout to finish: 2 out of 3 new replicas have been updated... Waiting for deployment "examplehttpapp" rollout to finish: 2 out of 3 new replicas have been updated... Waiting for deployment "examplehttpapp" rollout to finish: 1 old replicas are pending termination... Waiting for deployment "examplehttpapp" rollout to finish: 1 old replicas are pending termination... |
kubectl --record=true set image deployment examplehttpapp docker-http-server=katacoda/docker-http-server:v2 # deployment.extensions/examplehttpapp image updated kubectl rollout status deployment examplehttpapp # Waiting for deployment "examplehttpapp" rollout to finish: 1 out of 3 new replicas have been updated... # Waiting for deployment "examplehttpapp" rollout to finish: 1 out of 3 new replicas have been updated... # Waiting for deployment "examplehttpapp" rollout to finish: 1 out of 3 new replicas have been updated... # Waiting for deployment "examplehttpapp" rollout to finish: 2 out of 3 new replicas have been updated... # Waiting for deployment "examplehttpapp" rollout to finish: 2 out of 3 new replicas have been updated... # Waiting for deployment "examplehttpapp" rollout to finish: 2 out of 3 new replicas have been updated... # Waiting for deployment "examplehttpapp" rollout to finish: 1 old replicas are pending termination... # Waiting for deployment "examplehttpapp" rollout to finish: 1 old replicas are pending termination... |
| Line 552: | Line 553: |
| master $ kubectl rollout undo deployment examplehttpapp deployment.extensions/examplehttpapp rolled back |
kubectl rollout undo deployment examplehttpapp # deployment.extensions/examplehttpapp rolled back |
| Line 556: | Line 557: |
| master $ kubectl expose deployment examplehttpapp --port 80 service/examplehttpapp exposed master $ kubectl get svc -o wide NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR examplehttpapp ClusterIP 10.103.93.196 <none> 80/TCP 13s app=examplehttpapp kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 105m <none> master $ kubectl describe svc examplehttpapp Name: examplehttpapp Namespace: default Labels: app=examplehttpapp Annotations: <none> Selector: app=examplehttpapp Type: ClusterIP IP: 10.103.93.196 Port: <unset> 80/TCP TargetPort: 80/TCP Endpoints: 10.44.0.2:80,10.44.0.4:80,10.44.0.5:80 Session Affinity: None Events: <none> |
kubectl expose deployment examplehttpapp --port 80 # service/examplehttpapp exposed kubectl get svc -o wide # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR # examplehttpapp ClusterIP 10.103.93.196 <none> 80/TCP 13s app=examplehttpapp # kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 105m <none> kubectl describe svc examplehttpapp # Name: examplehttpapp # Namespace: default # Labels: app=examplehttpapp # Annotations: <none> # Selector: app=examplehttpapp # Type: ClusterIP # IP: 10.103.93.196 # Port: <unset> 80/TCP # TargetPort: 80/TCP # Endpoints: 10.44.0.2:80,10.44.0.4:80,10.44.0.5:80 # Session Affinity: None # Events: <none> |
| Line 577: | Line 578: |
| Each Object within Kubernetes can have a label attached, allowing Kubernetes to discover and use the configuration. master $ kubectl get services -l app=examplehttpapp -o go-template='{{(index .items 0).spec.clusterIP}}' 10.103.93.196master $ kubectl get services NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE examplehttpapp ClusterIP 10.103.93.196 <none> 80/TCP 2m32s kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 107m master $ kubectl get services -o wide NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR examplehttpapp ClusterIP 10.103.93.196 <none> 80/TCP 2m36s app=examplehttpapp kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 107m <none> |
# Each Object within Kubernetes can have a label attached, allowing Kubernetes to discover and use the configuration. kubectl get services -l app=examplehttpapp -o go-template='{{(index .items 0).spec.clusterIP}}' kubectl get services # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE # examplehttpapp ClusterIP 10.103.93.196 <none> 80/TCP 2m32s # kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 107m kubectl get services -o wide # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR # examplehttpapp ClusterIP 10.103.93.196 <none> 80/TCP 2m36s app=examplehttpapp # kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 107m <none> |
| Line 591: | Line 592: |
| master $ kubectl logs $(kubectl get pods -l app=examplehttpapp -o go-template='{{(index .items 0).metadata.name}}') Web Server started. Listening on 0.0.0.0:80 |
kubectl logs $(kubectl get pods -l app=examplehttpapp -o go-template='{{(index .items 0).metadata.name}}') # Web Server started. Listening on 0.0.0.0:80 |
| Line 595: | Line 596: |
| master $ kubectl top node NAME CPU(cores) CPU% MEMORY(bytes) MEMORY% master 133m 3% 1012Mi 53% node01 49m 1% 673Mi 17% master $ kubectl top pod NAME CPU(cores) MEMORY(bytes) examplehttpapp-58f66848-ctnml 0m 0Mi examplehttpapp-58f66848-gljk9 1m 0Mi examplehttpapp-58f66848-hfqts 1m 0Mi }}} == k3s - Lightweight Kubernetes == * https://k3s.io/ * https://github.com/rancher/k3s/releases/tag/v1.17.0+k3s.1 * https://rancher.com/docs/k3s/latest/en/ * https://rancher.com/docs/k3s/latest/en/quick-start/ K3S works great from something as small as a Raspberry Pi to an AWS a1.4xlarge 32GiB server. Download k3s - latest release, x86_64, ARMv7, and ARM64 are supported Situations where a PhD in k8s clusterology is infeasible {{{#!highlight bash curl -sfL https://get.k3s.io | sh - root@debian:/home/user# curl -sfL https://get.k3s.io | sh - [INFO] Finding latest release [INFO] Using v1.17.0+k3s.1 as release [INFO] Downloading hash https://github.com/rancher/k3s/releases/download/v1.17.0+k3s.1/sha256sum-amd64.txt [INFO] Downloading binary https://github.com/rancher/k3s/releases/download/v1.17.0+k3s.1/k3s [INFO] Verifying binary download [INFO] Installing k3s to /usr/local/bin/k3s [INFO] Creating /usr/local/bin/kubectl symlink to k3s [INFO] Creating /usr/local/bin/crictl symlink to k3s [INFO] Creating /usr/local/bin/ctr symlink to k3s [INFO] Creating killall script /usr/local/bin/k3s-killall.sh [INFO] Creating uninstall script /usr/local/bin/k3s-uninstall.sh [INFO] env: Creating environment file /etc/systemd/system/k3s.service.env [INFO] systemd: Creating service file /etc/systemd/system/k3s.service [INFO] systemd: Enabling k3s unit Created symlink /etc/systemd/system/multi-user.target.wants/k3s.service → /etc/systemd/system/k3s.service. [INFO] systemd: Starting k3s root@debian:/home/user# k3s kubectl cluster-info kubectl create deployment springboot-test --image=vbodocker/springboot-test:latest kubectl expose deployment springboot-test --port=8000 --target-port=8080 --type=NodePort kubectl get services IP_SPRINGBOOT=$(kubectl get services | grep springboot | awk '//{print $3}') curl http://$IP_SPRINGBOOT:8000/dummy # list containerd images and containers k3s crictl images k3s crictl ps # connect to container id crictl exec -it 997a2ad8c763a sh # connect to container/pod kubectl get pods kubectl exec -it springboot-test-6bb5fdfc48-phh8k sh cat /etc/os-release # alpine linux in container # give sudo rights to user /sbin/usermod -aG sudo user # scale pods sudo kubectl scale deployment springboot-test --replicas=3 sudo kubectl get pods -o wide # add mariadb pod/service sudo kubectl create deployment mariadb-test --image=mariadb:latest sudo kubectl get pods -o wide sudo kubectl delete deployment mariadb-test # https://kubernetes.io/docs/tasks/run-application/run-single-instance-stateful-application/ sudo kubectl apply -f mariadb-pv.yaml #persistentvolume/mariadb-pv-volume created #persistentvolumeclaim/mariadb-pv-claim created sudo kubectl apply -f mariadb-deployment.yaml #service/mariadb created #deployment.apps/mariadb created sudo kubectl describe deployment mariadb sudo kubectl get svc -o wide # connect to mariabdb pod sudo kubectl exec -it mariadb-8578f4dc8c-r4ftv /bin/bash ss -atn # show ports tcp listening ip address # show ip addresses mysql -h localhost -p mysql -u root -h 10.42.0.12 -p # delete service, persistent volume claim and persistent volume sudo kubectl delete deployment,svc mariadb sudo kubectl delete pvc mariadb-pv-claim sudo kubectl delete pv mariadb-pv-volume }}} === mariadb-pv.yaml === {{{ apiVersion: v1 kind: PersistentVolume metadata: name: mariadb-pv-volume labels: type: local spec: storageClassName: manual capacity: storage: 1Gi accessModes: - ReadWriteOnce hostPath: path: "/mnt/data" --- apiVersion: v1 kind: PersistentVolumeClaim metadata: name: mariadb-pv-claim spec: storageClassName: manual accessModes: - ReadWriteOnce resources: requests: storage: 1Gi }}} === mariadb-deployment.yaml === {{{ apiVersion: v1 kind: Service metadata: name: mariadb spec: ports: - port: 3306 selector: app: mariadb clusterIP: None --- apiVersion: apps/v1 # for versions before 1.9.0 use apps/v1beta2 kind: Deployment metadata: name: mariadb spec: selector: matchLabels: app: mariadb strategy: type: Recreate template: metadata: labels: app: mariadb spec: containers: - image: mariadb:latest name: mariadb env: # Use secret in real usage - name: MYSQL_ROOT_PASSWORD value: password ports: - containerPort: 3306 name: mariadb volumeMounts: - name: mariadb-persistent-storage mountPath: /var/lib/mariadb volumes: - name: mariadb-persistent-storage persistentVolumeClaim: claimName: mariadb-pv-claim }}} == Init containers == * https://kubernetes.io/docs/concepts/workloads/pods/init-containers/ Init containers can contain utilities or setup scripts not present in an app image. == systemctl commands == * systemctl stop k3s * systemctl status k3s * systemctl disable k3s.service * systemctl stop mono-xsp4.service * systemctl disable mono-xsp4.service == Ubuntu pod == {{{#!highlight yaml #ubuntu.yaml apiVersion: v1 kind: Pod metadata: name: ubuntu labels: app: ubuntu spec: containers: - name: ubuntu image: ubuntu:latest command: ["/bin/sleep", "3650d"] imagePullPolicy: IfNotPresent restartPolicy: Always }}} {{{#!highlight bash sudo kubectl apply -f ubuntu.yaml sudo kubectl get pods sudo kubectl exec -it ubuntu -- bash sudo kubectl delete pod ubuntu }}} == Alpine pod == {{{#!highlight yaml #alpine.yaml apiVersion: v1 kind: Pod metadata: name: alpine labels: app: alpine spec: containers: - name: alpine image: alpine:latest command: ["/bin/sleep", "3650d"] imagePullPolicy: IfNotPresent restartPolicy: Always }}} {{{#!highlight bash # Pods use PersistentVolumeClaims to request physical storage. sudo kubectl apply -f alpine.yaml sudo kubectl exec -it alpine -- sh }}} == Nginx persistent volume == {{{#!highlight bash cd /tmp mkdir -p /tmp/data echo 'Hello from Kubernetes storage' > /tmp/data/index.html }}} {{{#!highlight yaml #pv-volume.yaml apiVersion: v1 kind: PersistentVolume metadata: name: task-pv-volume labels: type: local spec: storageClassName: manual capacity: storage: 0.2Gi accessModes: - ReadWriteOnce hostPath: path: "/tmp/data" }}} {{{#!highlight yaml # pv-claim.yaml apiVersion: v1 kind: PersistentVolumeClaim metadata: name: task-pv-claim spec: storageClassName: manual accessModes: - ReadWriteOnce resources: requests: storage: 0.2Gi }}} {{{#!highlight yaml # pv-pod.yaml apiVersion: v1 kind: Pod metadata: name: task-pv-pod spec: volumes: - name: task-pv-storage persistentVolumeClaim: claimName: task-pv-claim containers: - name: task-pv-container image: nginx ports: - containerPort: 80 name: "http-server" volumeMounts: - mountPath: "/usr/share/nginx/html" name: task-pv-storage }}} {{{#!highlight bash sudo kubectl apply -f pv-volume.yaml sudo kubectl apply -f pv-claim.yaml sudo kubectl apply -f pv-pod.yaml sudo kubectl get pods -o wide curl http://10.42.0.28/ sudo kubectl exec -it task-pv-pod -- bash cd /usr/share/nginx/html echo "Hey from Kubernetes storage" > index.html cat /etc/os-release # debian buster kubectl delete pod task-pv-pod kubectl delete pvc task-pv-claim kubectl delete pv task-pv-volume cat /tmp/data/index.html }}} == Generate yaml == * sudo kubectl create deployment cherrypy-test --image=vbodocker/cherrypy-test --dry-run=client --output=yaml * sudo kubectl expose deployment cherrypy-test --port=8080 --type=NodePort --dry-run=client --output=yaml * sudo kubectl scale deployment cherrypy-test --replicas=3 --dry-run=client --output=yaml == Alpine pertistent volume == {{{#!highlignt yaml $cat alpine-shared.yaml --- apiVersion: v1 kind: PersistentVolume metadata: name: alpine-pv-volume labels: type: local spec: storageClassName: manual capacity: storage: 0.2Gi accessModes: - ReadWriteOnce hostPath: path: "/tmp/alpine-data" --- apiVersion: v1 kind: PersistentVolumeClaim metadata: name: alpine-pv-claim spec: storageClassName: manual accessModes: - ReadWriteOnce resources: requests: storage: 0.2Gi --- apiVersion: v1 kind: Pod metadata: name: alpine-pod labels: app: alpine-pod spec: volumes: - name: alpine-pv-storage persistentVolumeClaim: claimName: alpine-pv-claim containers: - name: alpine image: alpine:latest command: ["/bin/sleep", "3650d"] imagePullPolicy: IfNotPresent volumeMounts: - mountPath: "/mnt/alpine/data" name: alpine-pv-storage restartPolicy: Always }}} {{{#!highlight bash sudo kubectl apply -f alpine-shared.yaml sudo kubectl exec -it alpine-pod -- sh /mnt/alpine/data # echo "teste" > x.txt # inside pode cat /tmp/alpine-data/x.txt # k8s host }}} |
kubectl top node # NAME CPU(cores) CPU% MEMORY(bytes) MEMORY% # master 133m 3% 1012Mi 53% # node01 49m 1% 673Mi 17% kubectl top pod # NAME CPU(cores) MEMORY(bytes) # examplehttpapp-58f66848-ctnml 0m 0Mi # examplehttpapp-58f66848-gljk9 1m 0Mi # examplehttpapp-58f66848-hfqts 1m 0Mi }}} == Shows mapping between services and pods == {{{#!highlight sh kubectl get endpoints }}} == Show events ordered by last timestamp ascending == {{{#!highlight sh kubectl get events --sort-by='.lastTimestamp' }}} |
kubernetes
Contents
-
kubernetes
- cluster details and health status
- get cluster nodes
- Deploy containers
- dashboard
- Init master
- Deploy cni weaveworks - deploy a pod network to the cluster
- Join cluster
- Deploy container in cluster
- Apply dashboard in cluster
- List services
- Start containers using Kubectl
- Certified kubernetes application developer
- Shows mapping between services and pods
- Show events ordered by last timestamp ascending
- deploy docker images in containers. Cluster has nodes. Nodes has pods/containers. Each cluster might correspond to a service.
- Ingress, An API object that manages external access to the services in a cluster, typically HTTP. Ideas like reverse-proxy and load balancer.
- minikube version # check version 1.2.0
- minikube start
1 minikube version
2 # minikube version: v1.2.0
3 minikube start
4 # * minikube v1.2.0 on linux (amd64)
5 # * Creating none VM (CPUs=2, Memory=2048MB, Disk=20000MB) ...
6 # * Configuring environment for Kubernetes v1.15.0 on Docker 18.09.5
7 # - kubelet.resolv-conf=/run/systemd/resolve/resolv.conf
8 # * Pulling images ...
9 # * Launching Kubernetes ...
10 #
11 # * Configuring local host environment ...
12 # * Verifying: apiserver proxy etcd scheduler controller dns
13 # * Done! kubectl is now configured to use "minikube"
14
cluster details and health status
get cluster nodes
Deploy containers
1 # deploy container
2 kubectl create deployment first-deployment --image=katacoda/docker-http-server
3 # deployment.apps/first-deployment created
4 # deploy container in cluster
5 # check pods
6 kubectl get pods
7 # NAME READY STATUS RESTARTS AGE
8 # first-deployment-8cbf74484-s2fkl 1/1 Running 0 25s
9 # expose deployment
10 kubectl expose deployment first-deployment --port=80 --type=NodePort
11 # service/first-deployment exposed
12
13 kubectl get svc first-deployment
14 # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
15 # first-deployment NodePort 10.98.246.87 <none> 80:31219/TCP 105s
16 # do request to port 80 in cluster ip
17 curl 10.98.246.87:80
18 # <h1>This request was processed by host: first-deployment-8cbf74484-s2fkl</h1>
19 #
20 curl host01:31219
21 # <h1>This request was processed by host: first-deployment-8cbf74484-s2fkl</h1>
22
dashboard
1 minikube addons enable dashboard
2 #The Kubernetes dashboard allows you to view your applications
3 # in a UI.
4 # * dashboard was successfully enabled
5 kubectl apply -f /opt/kubernetes-dashboard.yaml
6 # only in katacoda
7 # service/kubernetes-dashboard-katacoda created
8 # check progress
9 kubectl get pods -n kube-system -w #check progress
10 # NAME READY STATUS RESTARTS AGE
11 # coredns-5c98db65d4-b2kxm 1/1 Running 0 17m
12 # coredns-5c98db65d4-mm567 1/1 Running 1 17m
13 # etcd-minikube 1/1 Running 0 16m
14 # kube-addon-manager-minikube 1/1 Running 0 16m
15 # kube-apiserver-minikube 1/1 Running 0 16m
16 # kube-controller-manager-minikube 1/1 Running 0 16m
17 # kube-proxy-pngm9 1/1 Running 0 17m
18 # kube-scheduler-minikube 1/1 Running 0 16m
19 # kubernetes-dashboard-7b8ddcb5d6-xt5nt 1/1 Running 0 76s
20 # storage-provisioner 1/1 Running 0 17m
21
22 # dashboard url https://2886795294-30000-kitek05.environments.katacoda.com/
23 # how to launch a Single Node Kubernetes cluster.
24
Init master
1 master $ kubeadm init --kubernetes-version $(kubeadm version -o short)
2 [init] Using Kubernetes version: v1.14.0
3 [preflight] Running pre-flight checks
4 [preflight] Pulling images required for setting up a Kubernetes cluster
5 [preflight] This might take a minute or two, depending on the speed of your internet connection
6 [preflight] You can also perform this action in beforehand using 'kubeadm config images pull'
7 [kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
8 [kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
9 [kubelet-start] Activating the kubelet service
10 [certs] Using certificateDir folder "/etc/kubernetes/pki"
11 [certs] Generating "ca" certificate and key
12 [certs] Generating "apiserver" certificate and key
13 [certs] apiserver serving cert is signed for DNS names [master kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 172.17.0.69]
14 [certs] Generating "apiserver-kubelet-client" certificate and key
15 [certs] Generating "front-proxy-ca" certificate and key
16 [certs] Generating "front-proxy-client" certificate and key
17 [certs] Generating "etcd/ca" certificate and key
18 [certs] Generating "etcd/healthcheck-client" certificate and key
19 [certs] Generating "apiserver-etcd-client" certificate and key
20 [certs] Generating "etcd/server" certificate and key
21 [certs] etcd/server serving cert is signed for DNS names [master localhost] and IPs [172.17.0.69 127.0.0.1 ::1]
22 [certs] Generating "etcd/peer" certificate and key
23 [certs] etcd/peer serving cert is signed for DNS names [master localhost] and IPs [172.17.0.69 127.0.0.1 ::1]
24 [certs] Generating "sa" key and public key
25 [kubeconfig] Using kubeconfig folder "/etc/kubernetes"
26 [kubeconfig] Writing "admin.conf" kubeconfig file
27 [kubeconfig] Writing "kubelet.conf" kubeconfig file
28 [kubeconfig] Writing "controller-manager.conf" kubeconfig file
29 [kubeconfig] Writing "scheduler.conf" kubeconfig file
30 [control-plane] Using manifest folder "/etc/kubernetes/manifests"
31 [control-plane] Creating static Pod manifest for "kube-apiserver"
32 [control-plane] Creating static Pod manifest for "kube-controller-manager"
33 [control-plane] Creating static Pod manifest for "kube-scheduler"
34 [etcd] Creating static Pod manifest for local etcd in "/etc/kubernetes/manifests"
35 [wait-control-plane] Waiting for the kubelet to boot up the control plane as static Pods from directory "/etc/kubernetes/manifests". This can take up to 4m0s
36 [apiclient] All control plane components are healthy after 16.503433 seconds
37 [upload-config] storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system"Namespace
38 [kubelet] Creating a ConfigMap "kubelet-config-1.14" in namespace kube-system with the configuration for the kubelets in the cluster
39 [upload-certs] Skipping phase. Please see --experimental-upload-certs
40 [mark-control-plane] Marking the node master as control-plane by adding the label "node-role.kubernetes.io/master=''"
41 [mark-control-plane] Marking the node master as control-plane by adding the taints [node-role.kubernetes.io/master:NoSchedule]
42 [bootstrap-token] Using token: xfvno5.q2xfb2m3nw7grdjm
43 [bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles
44 [bootstrap-token] configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
45 [bootstrap-token] configured RBAC rules to allow the csrapprover controller automatically approveCSRs from a Node Bootstrap Token
46 [bootstrap-token] configured RBAC rules to allow certificate rotation for all node client certificates in the cluster
47 [bootstrap-token] creating the "cluster-info" ConfigMap in the "kube-public" namespace
48 [addons] Applied essential addon: CoreDNS
49 [addons] Applied essential addon: kube-proxy
50
51 Your Kubernetes control-plane has initialized successfully!
52
53 To start using your cluster, you need to run the following as a regular user:
54
55 mkdir -p $HOME/.kube
56 sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
57 sudo chown $(id -u):$(id -g) $HOME/.kube/config
58
59 You should now deploy a pod network to the cluster.
60 Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
61 https://kubernetes.io/docs/concepts/cluster-administration/addons/
62
63 Then you can join any number of worker nodes by running the following on each as root:
64
65 kubeadm join 172.17.0.69:6443 --token xfvno5.q2xfb2m3nw7grdjm \
66 --discovery-token-ca-cert-hash sha256:26d11c038d236967630d401747f210af9e3679fb1638e8b599a2da4cb98ab159
Deploy cni weaveworks - deploy a pod network to the cluster
Container Network Interface (CNI) defines how the different nodes and their workloads should communicate. Weave Net provides a network to connect all pods together, implementing the Kubernetes model. Kubernetes uses the Container Network Interface (CNI) to join pods onto Weave Net.
1 # In master
2 kubectl apply -f /opt/weave-kube
3 # serviceaccount/weave-net created
4 # clusterrole.rbac.authorization.k8s.io/weave-net created
5 # clusterrolebinding.rbac.authorization.k8s.io/weave-net created
6 # role.rbac.authorization.k8s.io/weave-net created
7 # rolebinding.rbac.authorization.k8s.io/weave-net created
8 # daemonset.extensions/weave-net created
9 kubectl get pod -n kube-system
10 # NAME READY STATUS RESTARTS AGE
11 # coredns-fb8b8dccf-b9rd7 1/1 Running 0 11m
12 # coredns-fb8b8dccf-sfgbn 1/1 Running 0 11m
13 # etcd-master 1/1 Running 0 10m
14 # kube-apiserver-master 1/1 Running 0 10m
15 # kube-controller-manager-master 1/1 Running 0 10m
16 # kube-proxy-l42wp 1/1 Running 0 11m
17 # kube-scheduler-master 1/1 Running 1 10m
18 # weave-net-mcxml 2/2 Running 0 84s
19
Join cluster
1 # in node01
2 # join cluster
3 kubeadm join --discovery-token-unsafe-skip-ca-verification --token=xfvno5.q2xfb2m3nw7grdjm 172.17.0.69:6443
4 # [preflight] Running pre-flight checks
5 # [preflight] Reading configuration from the cluster...
6 # [preflight] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -oyaml'
7 # [kubelet-start] Downloading configuration for the kubelet from the "kubelet-config-1.14" ConfigMap in the kube-system namespace
8 # [kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml"
9 # [kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env"
10 # [kubelet-start] Activating the kubelet service
11 # [kubelet-start] Waiting for the kubelet to perform the TLS Bootstrap...
12 #
13 # This node has joined the cluster:
14 # * Certificate signing request was sent to apiserver and a response was received.
15 # * The Kubelet was informed of the new secure connection details.
16 #
17 # Run 'kubectl get nodes' on the control-plane to see this node join the cluster.
18 # The --discovery-token-unsafe-skip-ca-verification tag is used to bypass the Discovery Token verification.
19
20 # in master
21 kubectl get nodes
22 # NAME STATUS ROLES AGE VERSION
23 # master Ready master 17m v1.14.0
24 # node01 Ready <none> 107s v1.14.0
25 # bootstrap token generated b
26
27 # in node01
28 kubectl get nodes
29 # The connection to the server localhost:8080 was refused - did you specify the right host or port
30
Deploy container in cluster
1 # In master
2 kubectl create deployment http --image=katacoda/docker-http-server:latest
3 # deployment.apps/http created
4 kubectl get pods
5 # NAME READY STATUS RESTARTS AGE
6 # http-7f8cbdf584-74pd9 1/1 Running 0 11s
7 docker ps | grep http-server
8
9 # In node01
10 docker ps | grep http-serveradb3cde7f861
11 # katacoda/docker-http-server "/app"
12 # About a minute ago
13 # Up About a minute k8s_docker-http-server_http-7f8cbdf584-74pd9_default_04a
14 # 17065-b08d-11e9-bff1-0242ac110045_0
15
16 # expose deployment in master
17 kubectl get pods
18 # NAME READY STATUS RESTARTS AGE
19 # http-7f8cbdf584-74pd9 1/1 Running 0 17m bootstrap # token generated b
20 kubectl expose deployment http --port=80 --type=NodePort
21 # service/http exposed
22
23 kubectl get service http
24 # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
25 # http NodePort 10.101.65.149 <none> 80:30982/TCP 49s
26
27 curl 10.101.65.149:80
28 # <h1>This request was processed by host: http-7f8cbdf584-74pd9</h1>
29
30 curl http://10.101.65.149
31 # <h1>This request was processed by host: http-7f8cbdf584-74pd9</h1>
32
Apply dashboard in cluster
- Dashboard General-purpose web UI for Kubernetes clusters Dashboard Version: v1.10.0
1 # In master
2 kubectl apply -f dashboard.yaml
3 # secret/kubernetes-dashboard-certs created
4 # serviceaccount/kubernetes-dashboard created
5 # role.rbac.authorization.k8s.io/kubernetes-dashboard-minimal created
6 # rolebinding.rbac.authorization.k8s.io/kubernetes-dashboard-minimal created
7 # deployment.apps/kubernetes-dashboard created
8 # service/kubernetes-dashboard created
9 kubectl get pods -n kube-system
10 # NAME READY STATUS RESTARTS AGEcoredns-fb8b8dccf-b9rd7 # 1/1 Running 0 42mcoredns-fb8b8dccf-sfgbn 1/1 Running # 0 42m
11 # etcd-master 1/1 Running 0 41m
12 # kube-apiserver-master 1/1 Running 0 40m
13 # kube-controller-manager-master 1/1 Running 0 40m
14 # kube-proxy-gwrps 1/1 Running 0 26m
15 # kube-proxy-l42wp 1/1 Running 0 42m
16 # kube-scheduler-master 1/1 Running 1 40m
17 # kubernetes-dashboard-5f57845f9d-ls7q2 0/1 ContainerCreating 0 2s
18 # weave-net-gww8b 2/2 Running 0 26m
19 # weave-net-mcxml 2/2 Running 0 31m
20
Create service account for dashboard
1 cat <<EOF | kubectl create -f -
2 apiVersion: v1
3 kind: ServiceAccount
4 metadata:
5 name: admin-user
6 namespace: kube-system
7 ---
8 apiVersion: rbac.authorization.k8s.io/v1beta1
9 kind: ClusterRoleBinding
10 metadata:
11 name: admin-user
12 roleRef:
13 apiGroup: rbac.authorization.k8s.io
14 kind: ClusterRole
15 name: cluster-admin
16 subjects:
17 - kind: ServiceAccount
18 name: admin-user
19 namespace: kube-system
20 EOF
21
22 # Get login token
23 kubectl -n kube-system describe secret $(kubectl -n kube-system get secret | grep admin-user | awk '{print $1}')
24
25 When the dashboard was deployed, it used externalIPs to bind the service to port 8443. This makes the dashboard available to outside of the cluster and viewable at https://2886795335-8443-kitek05.environments.katacoda.com/
26
27 # Use the admin-user token to access the dashboard.
28 https://2886795335-8443-kitek05.environments.katacoda.com/#!/login
29 # sign in using token
30 eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJrdWJlLXN5c3RlbSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VjcmV0Lm5hbWUiOiJhZG1pbi11c2VyLXRva2VuLXNzcTl4Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9zZXJ2aWNlLWFjY291bnQubmFtZSI6ImFkbWluLXVzZXIiLCJrdWJlcm5ldGVzLmlvL3NlcnZpY2VhY2NvdW50L3NlcnZpY2UtYWNjb3VudC51aWQiOiI2Y2RiNGZmMy1iMDkwLTExZTktYmZmMS0wMjQyYWMxMTAwNDUiLCJzdWIiOiJzeXN0ZW06c2VydmljZWFjY291bnQ6a3ViZS1zeXN0ZW06YWRtaW4tdXNlciJ9.R2OtDYxXaR0Pgluzq1m8FMZflF2tdYtJdG5XhkVC28vf1WkJu-Zo51I5ONUiK2WdBEMPw-N2PW_R9l6lak1clvlxfUSn777nThYSxhmR5pfxi6GmDlFo928KJvWVPDen1jrzAaQOEUZ1maOzPcnjKGpR-CRTgmYDnxZY84rqi68y0vfdn16ER8HeW-wkJ-hfGyUAhryk_ob1CUBjjbs-vefpaLcHLdrWNaKaFi1j5fCc_eJi10FpSTmuBsb04xgN0I17hkTlSw2fyOAj7LtC3pBDrK0nOdHCJkBEtsg89rkvLufYph5AFeoWQVKdW9JZH8BYS91BFla7pZnTwdBVeA
31
32 https://2886795335-8443-kitek05.environments.katacoda.com/#!/overview?namespace=default
List services
Start containers using Kubectl
1 minikube start # start kubernetes cluster and its components
2 # * minikube v1.2.0 on linux (amd64)
3 # * Creating none VM (CPUs=2, Memory=2048MB, Disk=20000MB) ...
4 # * Configuring environment for Kubernetes v1.15.0 on Docker 18.09.5
5 # - kubelet.resolv-conf=/run/systemd/resolve/resolv.conf
6 # * Pulling images ...
7 # * Launching Kubernetes ...
8 # * Configuring local host environment ...
9 # * Verifying: apiserver proxy etcd
10 #
11 # scheduler controller dns
12 # * Done! kubectl is now configured to use "minikube"
13 kubectl get nodes
14 # NAME STATUS ROLES AGE VERSION
15 # minikube Ready master 2m2s v1.15.0
16
17 kubectl get service
18 # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
19 # kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 2m18s
20 # This deployment is issued to the Kubernetes master which launches the Pods and containers required. Kubectl run_ is similar to docker run but at a cluster
21 level.
22 # launch a deployment called http which will start a container based on the Docker Image katacoda/docker-http-server:latest.
23 kubectl run http --image=katacoda/docker-http-server:latest --replicas=1
24 # kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version.Use kubectl run --generator=run-pod/v1 or kubectl create instead.
25 # deployment.apps/http created
26 kubectl get deployments
27 # NAME READY UP-TO-DATE AVAILABLE AGE
28 # http 1/1 1 1 6s
29
30 # you can describe the deployment process.
31 kubectl describe deployment http
32
33 # expose the container port 80 on the host 8000 binding to the external-ip of the host.
34 kubectl expose deployment http --external-ip="172.17.0.13" --port=8000 --target-port=80
35 # service/http exposed
36
37 curl http://172.17.0.13:8000
38 # <h1>This request was processed by host: http-5fcf9dd9cb-zfkkz</h1>
39
40 kubectl get pods
41 # NAME READY STATUS RESTARTS AGE
42 # http-5fcf9dd9cb-zfkkz 1/1 Running 0 3m26s
43
44 kubectl get service
45 # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
46 # http ClusterIP 10.100.157.159 172.17.0.13 8000/TCP 57s
47 # kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 7m41s
48
49 curl http://10.100.157.159:8000
50 # <h1>This request was processed by host: http-5fcf9dd9cb-zfkkz</h1>
51
52 kubectl run httpexposed --image=katacoda/docker-http-server:latest --replicas=1 --port=80 --host
53 port=8001
54 # kubectl run --generator=deployment/apps.v1 is DEPRECATED and will be removed in a future version.
55 # Use kubectl run --generator=run-pod/v1 or kubectl create instead.
56 # deployment.apps/httpexposed created
57 curl http://172.17.0.13:8001
58 # <h1>This request was processed by host: httpexposed-569df5d86-rzzhb</h1>
59 kubectl get svc
60 # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
61 # http ClusterIP 10.100.157.159 172.17.0.13 8000/TCP 3m50s
62 # kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 10m
63
64 kubectl get pods
65 # NAME READY STATUS RESTARTS AGE
66 # http-5fcf9dd9cb-zfkkz 1/1 Running 0 7m9s
67 # httpexposed-569df5d86-rzzhb 1/1 Running 0 36s
68
69 # Scaling the deployment will request Kubernetes to launch additional Pods.
70 kubectl scale --replicas=3 deployment http
71 # deployment.extensions/http scaled
72
73 kubectl get pods # amount of pods for service http increased to 3
74 # NAME READY STATUS RESTARTS AGE
75 # http-5fcf9dd9cb-fhljh 1/1 Running 0 31s
76 # http-5fcf9dd9cb-wb2dh 1/1 Running 0 31s
77 # http-5fcf9dd9cb-zfkkz 1/1 Running 0 9m27s
78 # httpexposed-569df5d86-rzzhb 1/1 Running 0 2m54s
79
80 # Once each Pod starts it will be added to the load balancer service.
81 kubectl get service
82 # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
83 # http ClusterIP 10.100.157.159 172.17.0.13 8000/TCP 7m28s
84 # kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 14m
85
86 kubectl describe svc http
87 # Name: http
88 # Namespace: defaultLabels: run=httpAnnotations: <none>
89 # Selector: run=httpType: ClusterIPIP: 10.100.157.159
90 # External IPs: 172.17.0.13
91 # Port: <unset> 8000/TCP
92 # TargetPort: 80/TCP
93 # Endpoints: 172.18.0.4:80,172.18.0.6:80,172.18.0.7:80
94 # Session Affinity: None
95 # Events: <none>
96
97 curl http://172.17.0.13:8000
98 # <h1>This request was processed by host: http-5fcf9dd9cb-wb2dh</h1>
99 curl http://172.17.0.13:8000
100 # <h1>This request was processed by host: http-5fcf9dd9cb-fhljh</h1>
101 curl http://172.17.0.13:8000
102 # <h1>This request was processed by host: http-5fcf9dd9cb-zfkkz</h1>
103
Certified kubernetes application developer
1 # In master
2 launch.sh
3 # Waiting for Kubernetes to start...
4 # Kubernetes started
5 kubectl get nodes
6 # NAME STATUS ROLES AGE VERSION
7 # master Ready master 85m v1.14.0
8 # node01 Ready <none> 85m v1.14.0
9
10 # deploy app
11 kubectl create deployment examplehttpapp --image=katacoda/docker-http-server
12 # deployment.apps/examplehttpapp created
13
14 # view all deployments
15 kubectl get deployments
16 # NAME READY UP-TO-DATE AVAILABLE AGE
17 # examplehttpapp 1/1 1 1 25s
18
19 # A deployment will launch a set of Pods. A pod is a group of one or more containers deployed across the cluster.
20 kubectl get pods
21 # NAME READY STATUS RESTARTS AGE
22 # examplehttpapp-58f66848-n7wn7 1/1 Running 0 71s
23
24 # show pod ip and node where it is
25 kubectl get pods -o wide
26 # NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE # READINESS GATES
27 # examplehttpapp-58f66848-n7wn7 1/1 Running 0 113s 10.44.0.2 node01 <none> <none>
28
29 # describe pod
30 kubectl describe pod examplehttpapp-58f66848-n7wn7
31 # Name: examplehttpapp-58f66848-n7wn7
32 # Namespace: default
33 # Priority: 0
34 # PriorityClassName: <none>
35 # Node: node01/172.17.0.24
36 # Start Time: Sat, 27 Jul 2019 17:59:35 +0000
37 # Labels: app=examplehttpapp
38 # pod-template-hash=58f66848
39 # Annotations: <none>
40 # Status: Running
41 # IP: 10.44.0.2
42
43 # List all namespaces with in the cluster with
44 kubectl get namespaces
45 kubectl get ns
46
47 # The namespaces can be used to filter queries to the available objects.
48 kubectl get pods -n kube-system
49
50 kubectl create ns testns
51 # namespace/testns created
52 kubectl create deployment namespacedeg -n testns --image=katacoda/docker-http-server
53 # deployment.apps/namespacedeg created
54 kubectl get pods -n testns
55 # NAME READY STATUS RESTARTS AGE
56 # namespacedeg-74dcc7dc64-wcxnj 1/1 Running 0 3s
57 kubectl get pods -n testns -o wide
58 # NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
59 # namespacedeg-74dcc7dc64-wcxnj 1/1 Running 0 18s 10.44.0.3 node01 <none> <none>
60
61 # Kubectl can help scale the number of Pods running for a deployment, referred to as replicas.
62 kubectl scale deployment examplehttpapp --replicas=5
63 # deployment.extensions/examplehttpapp scaled
64 kubectl get deployments -o wide
65 # NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
66 # examplehttpapp 5/5 5 5 9m6s docker-http-server katacoda/docker-http-server app=examplehttpapp
67 kubectl get pods -o wide
68 # NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
69 # examplehttpapp-58f66848-cf6pl 1/1 Running 0 65s 10.44.0.6 node01 <none> <none>
70 # examplehttpapp-58f66848-lfrq4 1/1 Running 0 65s 10.44.0.5 node01 <none> <none>
71 # examplehttpapp-58f66848-n7wn7 1/1 Running 0 9m26s 10.44.0.2 node01 <none> <none>
72 # examplehttpapp-58f66848-snwl7 1/1 Running 0 65s 10.44.0.7 node01 <none> <none>
73 # examplehttpapp-58f66848-vd8db 1/1 Running 0 65s 10.44.0.4 node01 <none> <none>
74
75 # everything within Kubernetes is controllable as YAML.
76 kubectl edit deployment examplehttpapp # opens vi/vim, changing the spec.replicas to 10 after saving the file increased the number of pods
77
78 kubectl get nodes -o wide
79 # NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME
80 # master Ready master 102m v1.14.0 172.17.0.19 <none> Ubuntu 16.04.6 LTS 4.4.0-150-generic docker://18.9.5
81 # node01 Ready <none> 102m v1.14.0 172.17.0.24 <none> Ubuntu 16.04.6 LTS 4.4.0-150-generic docker://18.9.5
82
83 # Image can be changed using the set image command, rollout
84 # apply new image to the pods/containers
85 kubectl --record=true set image deployment examplehttpapp docker-http-server=katacoda/docker-http-server:v2
86 # deployment.extensions/examplehttpapp image updated
87 kubectl rollout status deployment examplehttpapp
88 # Waiting for deployment "examplehttpapp" rollout to finish: 1 out of 3 new replicas have been updated...
89 # Waiting for deployment "examplehttpapp" rollout to finish: 1 out of 3 new replicas have been updated...
90 # Waiting for deployment "examplehttpapp" rollout to finish: 1 out of 3 new replicas have been updated...
91 # Waiting for deployment "examplehttpapp" rollout to finish: 2 out of 3 new replicas have been updated...
92 # Waiting for deployment "examplehttpapp" rollout to finish: 2 out of 3 new replicas have been updated...
93 # Waiting for deployment "examplehttpapp" rollout to finish: 2 out of 3 new replicas have been updated...
94 # Waiting for deployment "examplehttpapp" rollout to finish: 1 old replicas are pending termination...
95 # Waiting for deployment "examplehttpapp" rollout to finish: 1 old replicas are pending termination...
96 deployment "examplehttpapp" successfully rolled out
97
98 # rollback deployment
99 kubectl rollout undo deployment examplehttpapp
100 # deployment.extensions/examplehttpapp rolled back
101
102 # The expose command will create a new service for a deployment. The port specifies the port of the application we want to available
103 kubectl expose deployment examplehttpapp --port 80
104 # service/examplehttpapp exposed
105 kubectl get svc -o wide
106 # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
107 # examplehttpapp ClusterIP 10.103.93.196 <none> 80/TCP 13s app=examplehttpapp
108 # kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 105m <none>
109 kubectl describe svc examplehttpapp
110 # Name: examplehttpapp
111 # Namespace: default
112 # Labels: app=examplehttpapp
113 # Annotations: <none>
114 # Selector: app=examplehttpapp
115 # Type: ClusterIP
116 # IP: 10.103.93.196
117 # Port: <unset> 80/TCP
118 # TargetPort: 80/TCP
119 # Endpoints: 10.44.0.2:80,10.44.0.4:80,10.44.0.5:80
120 # Session Affinity: None
121 # Events: <none>
122
123 # But how does Kubernetes know where to send traffic? That is managed by Labels.
124 # Each Object within Kubernetes can have a label attached, allowing Kubernetes to discover and use the configuration.
125
126 kubectl get services -l app=examplehttpapp -o go-template='{{(index .items 0).spec.clusterIP}}'
127 kubectl get services
128 # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
129 # examplehttpapp ClusterIP 10.103.93.196 <none> 80/TCP 2m32s
130 # kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 107m
131
132 kubectl get services -o wide
133 # NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
134 # examplehttpapp ClusterIP 10.103.93.196 <none> 80/TCP 2m36s app=examplehttpapp
135 # kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 107m <none>
136
137 # kubectl logs to to view the logs for Pods
138 kubectl logs $(kubectl get pods -l app=examplehttpapp -o go-template='{{(index .items 0).metadata.name}}')
139 # Web Server started. Listening on 0.0.0.0:80
140
141 # view the CPU or Memory usage of a node or Pod
142 kubectl top node
143 # NAME CPU(cores) CPU% MEMORY(bytes) MEMORY%
144 # master 133m 3% 1012Mi 53%
145 # node01 49m 1% 673Mi 17%
146 kubectl top pod
147 # NAME CPU(cores) MEMORY(bytes)
148 # examplehttpapp-58f66848-ctnml 0m 0Mi
149 # examplehttpapp-58f66848-gljk9 1m 0Mi
150 # examplehttpapp-58f66848-hfqts 1m 0Mi
151
Shows mapping between services and pods
1 kubectl get endpoints
Show events ordered by last timestamp ascending
1 kubectl get events --sort-by='.lastTimestamp'