在管理容器化应用方面，Kubernetes是目前最好的工具之一。而Minikube能够在macOS、Linux和Windows平台上实现一个本地Kubernetes集群，用于Kubernetes的学习。
Minikube是由Go语言实现，当前支持如下Kubernetes特性：
- DNS
- NodePort
- ConfigMap和Secret
- 仪表盘
- 容器运行时: Docker、rkt、CRI-O和containerd
- 使能容器网络接口
- Ingres
由上图可知，要使用Minikube，需要安装Minikube、kubectl和虚拟机。好在有Katacoda提供浏览器内的带有Kubernetes环境的免费虚拟终端，省却了安装这一步骤。
按照Kubernetes的Hello Minikube教程走了一遍。
minikube version; minikube start
$
$ minikube version; minikube start
minikube version: v0.28.2
Starting local Kubernetes v1.10.0 cluster...
Starting VM...
Getting VM IP address...
Moving files into cluster...
Setting up certs...
Connecting to cluster...
Setting up kubeconfig...
Starting cluster components...
Kubectl is now configured to use the cluster.
Loading cached images from config file.
$
$ minikube --help
Minikube is a CLI tool that provisions and manages single-node Kubernetes clusters optimized for development workflows.
Usage:
minikube [command]
Available Commands:
addons Modify minikube's kubernetes addons
cache Add or delete an image from the local cache.
completion Outputs minikube shell completion for the given shell (bash or zsh)
config Modify minikube config
dashboard Opens/displays the kubernetes dashboard URL for your local cluster
delete Deletes a local kubernetes cluster
docker-env Sets up docker env variables; similar to '$(docker-machine env)'
get-k8s-versions Gets the list of Kubernetes versions available for minikube when using the localkube bootstrapper
help Help about any command
ip Retrieves the IP address of the running cluster
logs Gets the logs of the running localkube instance, used for debugging minikube, not user code
mount Mounts the specified directory into minikube
profile Profile sets the current minikube profile
service Gets the kubernetes URL(s) for the specified service in your local cluster
ssh Log into or run a command on a machine with SSH; similar to 'docker-machine ssh'
ssh-key Retrieve the ssh identity key path of the specified cluster
start Starts a local kubernetes cluster
status Gets the status of a local kubernetes cluster
stop Stops a running local kubernetes cluster
update-check Print current and latest version number
update-context Verify the IP address of the running cluster in kubeconfig.
version Print the version of minikube
Flags:
--alsologtostderr log to standard error as well as files
-b, --bootstrapper string The name of the cluster bootstrapper that will set up the kubernetes cluster. (default "kubeadm")
-h, --help help for minikube
--log_backtrace_at traceLocation when logging hits line file:N, emit a stack trace (default :0)
--log_dir string If non-empty, write log files in this directory
--loglevel int Log level (0 = DEBUG, 5 = FATAL) (default 1)
--logtostderr log to standard error instead of files
-p, --profile string The name of the minikube VM being used.
This can be modified to allow for multiple minikube instances to be run independently (default "minikube")
--stderrthreshold severity logs at or above this threshold go to stderr (default 2)
-v, --v Level log level for V logs
--vmodule moduleSpec comma-separated list of pattern=N settings for file-filtered logging
Use "minikube [command] --help" for more information about a command.
$
$ minikube status
minikube: Running
cluster: Running
kubectl: Correctly Configured: pointing to minikube-vm at 172.17.0.48
$ minikube dashboard
Opening kubernetes dashboard in default browser...
$ kubectl create deployment hello-node --image=gcr.io/hello-minikube-zero-install/hello-node
deployment.apps/hello-node created
$ kubectl get deployments
NAME DESIRED CURRENT UP-TO-DATE AVAILABLE AGE
hello-node 1 1 1 0 6s
$ kubectl get deployments
NAME DESIRED CURRENT UP-TO-DATE AVAILABLE AGE
hello-node 1 1 1 1 1m
$ kubectl get pods
NAME READY STATUS RESTARTS AGE
hello-node-7f5b6bd6b8-xsv8q 1/1 Running 0 1m
$ kubectl get events
LAST SEEN FIRST SEEN COUNT NAME KIND SUBOBJECT TYPE REASON SOURCE MESSAGE
8m 8m 1 minikube.15a7b294ca3e3206 Node Normal Starting kubelet, minikube Starting kubelet.
8m 8m 1 minikube.15a7b294fd3f5d0a Node Normal Starting kube-proxy, minikube Starting kube-proxy.
8m 8m 1 minikube.15a7b294d0df5af8 Node Normal NodeHasSufficientPID kubelet, minikube Node minikube status is now: NodeHasSufficientPID
8m 8m 1 minikube.15a7b294d0df44a0 Node Normal NodeHasNoDiskPressure kubelet, minikube Node minikube status is now: NodeHasNoDiskPressure
8m 8m 1 minikube.15a7b294d0df2ab9 Node Normal NodeHasSufficientMemory kubelet, minikube Node minikube status is now: NodeHasSufficientMemory
8m 8m 1 minikube.15a7b294d0df04be Node Normal NodeHasSufficientDisk kubelet, minikube Node minikube status is now: NodeHasSufficientDisk
8m 8m 1 minikube.15a7b2954df56145 Node Normal NodeAllocatableEnforced kubelet, minikube Updated Node Allocatable limit across pods
8m 8m 1 minikube.15a7b2972a0b97fc Node Normal NodeReady kubelet, minikube Node minikube status is now: NodeReady
1m 1m 1 hello-node.15a7b2f9dca4ac42 Deployment Normal ScalingReplicaSet deployment-controller Scaled up replica set hello-node-7f5b6bd6b8 to 1
1m 1m 1 hello-node-7f5b6bd6b8.15a7b2f9dcb8c32e ReplicaSet Normal SuccessfulCreate replicaset-controller Created pod: hello-node-7f5b6bd6b8-xsv8q
1m 1m 1 hello-node-7f5b6bd6b8-xsv8q.15a7b2f9fe7cf48f Pod spec.containers{hello-node} Normal Pulling kubelet, minikube pulling image "gcr.io/hello-minikube-zero-install/hello-node"
1m 1m 1 hello-node-7f5b6bd6b8-xsv8q.15a7b2f9ef33a6b7 Pod Normal SuccessfulMountVolume kubelet, minikube MountVolume.SetUp succeeded for volume "default-token-kmdrg"
1m 1m 1 hello-node-7f5b6bd6b8-xsv8q.15a7b2f9dda4da8c Pod Normal Scheduled default-scheduler Successfully assigned hello-node-7f5b6bd6b8-xsv8q to minikube
59s 59s 1 hello-node-7f5b6bd6b8-xsv8q.15a7b301584221b0 Pod spec.containers{hello-node} Normal Started kubelet, minikube Started container
59s 59s 1 hello-node-7f5b6bd6b8-xsv8q.15a7b301517672cd Pod spec.containers{hello-node} Normal Created kubelet, minikube Created container
59s 59s 1 hello-node-7f5b6bd6b8-xsv8q.15a7b3014df0fe95 Pod spec.containers{hello-node} Normal Pulled kubelet, minikube Successfully pulled image "gcr.io/hello-minikube-zero-install/hello-node"
$ kubectl config view
apiVersion: v1
clusters:
- cluster:
certificate-authority: /root/.minikube/ca.crt
server: https://172.17.0.48:8443
name: minikube
contexts:
- context:
cluster: minikube
user: minikube
name: minikube
current-context: minikube
kind: Config
preferences: {}
users:
- name: minikube
user:
client-certificate: /root/.minikube/client.crt
client-key: /root/.minikube/client.key
$ kubectl expose deployment hello-node --type=LoadBalancer --port=8080
service/hello-node exposed
$ kubectl get services
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
hello-node LoadBalancer 10.103.104.233 <pending> 8080:31739/TCP 4s
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 9m
$ minikube service hello-node
Opening kubernetes service default/hello-node in default browser...
$ minikube addons list
- addon-manager: enabled
- coredns: disabled
- dashboard: enabled
- default-storageclass: enabled
- efk: disabled
- freshpod: disabled
- heapster: disabled
- ingress: disabled
- kube-dns: enabled
- metrics-server: disabled
- nvidia-driver-installer: disabled
- nvidia-gpu-device-plugin: disabled
- registry: disabled
- registry-creds: disabled
- storage-provisioner: enabled
$ minikube addons enable heapster
heapster was successfully enabled
$ kubectl get pod,svc -n kube-system
NAME READY STATUS RESTARTS AGE
pod/heapster-2mztm 1/1 Running 0 3m
pod/influxdb-grafana-v5j5q 2/2 Running 0 3m
pod/kube-addon-manager-minikube 1/1 Running 0 17m
pod/kube-dns-6dcb57bcc8-84zs7 3/3 Running 0 17m
pod/kubernetes-dashboard-5498ccf677-xc4kr 1/1 Running 0 17m
pod/storage-provisioner 1/1 Running 0 17m
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/heapster ClusterIP 10.107.109.88 <none> 80/TCP 3m
service/kube-dns ClusterIP 10.96.0.10 <none> 53/UDP,53/TCP 17m
service/kubernetes-dashboard NodePort 10.111.86.255 <none> 80:30000/TCP 17m
service/monitoring-grafana NodePort 10.111.167.239 <none> 80:30002/TCP 3m
service/monitoring-influxdb ClusterIP 10.98.229.238 <none> 8083/TCP,8086/TCP 3m
$ minikube addons disable heapster
heapster was successfully disabled
$ kubectl delete service hello-node
service "hello-node" deleted
$ kubectl delete deployment hello-node
deployment.extensions "hello-node" deleted
$ minikube stop
Stopping local Kubernetes cluster...
Machine stopped.
$
唯一要注意的是，教程里提到打开Kubernetes仪表盘使用Select port to view on Host 1菜单，结果是502 Bad GateWay错误。可使用View HTTP port 80 on Host 1然后修改端口为30000即可。
使用Katacoda，下列命令也可以一试。
minikube ip # Get IP address of the running cluster
kubectl cluster-info # Get cluster information
minikube dashboard --url # Get the Dashboard URL
minikube service --url SERVICE # Get the URL of service
参考
Install Minikube
Installing Kubernetes with Minikube
Kubernetes NodePort vs LoadBalancer vs Ingress? When should I use what?
MINIKUBE CHEATSHEET
Minikube体验
Minikube: easily run Kubernetes locally