OpenShiftばかり触ってて実はKubernetesの環境を持っていないので、Minishiftと同じように、K8sのオールインワンのmini環境を構築できるMinikubeを使って最小構成クラスタを構築してみる。
基本はInstall Minikube - Kubernetesの通りに作業すれば特に問題なく構築できる。
何番煎じかはわからない←
環境
| 項目 | 内容 |
|---|---|
| ホストOS | Windows 10 Home |
| ハイパーバイザ | VirtualBox 5.2.26 |
| Minikube | v0.35.0 |
| kubectl | v1.13.0 |
インストール
Windows 10 Homeでの構築なので、別途VirtualBoxを導入しておく。(Win10Proであれば、Hyper-Vで動くはず)
Minikubeのインストール
Windows版はインストーラもあるけど、ひとまずマニュアルインストールを試す。
Install Minikube / Windows manual installationから、minikube-windows-amd64のWindows版exeファイルをダウンロードする(記事作成時点でv0.35.0)
ダウンロードしたらminikube-windows-amd64.exeをminikube.exeにリネームし、パスの通ったディレクトリへ配置する。
実行確認
Windows PowerShell
Copyright (C) Microsoft Corporation. All rights reserved.
PS C:\Users\zaki> minikube version
minikube version: v0.35.0
PS C:\Users\zaki>
kubectlのインストール
(Minishiftと違って)Minikube環境ではCLIツールであるkubectlコマンドは同梱されていないらしいので、別途セットアップする。
Install and Set Up kubectl - Kubernetes
PowerShellやChocolateyを使った手順も載っているが、もっとも単純な、実行バイナリを直接ダウンロードする手順で取得する。
PowerShellで以下実行 (コマンドの意味はこちら)
PS C:\local\kubectl-v1.13.0-amd64> Invoke-WebRequest https://storage.googleapis.com/kubernetes-release/release/v1.13.0/bin/windows/amd64/kubectl.exe -OutFile kubectl.exe
パスを追加
実行確認
PS C:\Users\zaki> kubectl version
Client Version: version.Info{Major:"1", Minor:"13", GitVersion:"v1.13.0", GitCommit:"ddf47ac13c1a9483ea035a79cd7c10005ff21a6d", GitTreeState:"clean", BuildDate:"2018-12-03T21:04:45Z", GoVersion:"go1.11.2", Compiler:"gc", Platform:"windows/amd64"}
Unable to connect to the server: dial tcp 192.168.99.103:8443: connectex: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.
PS C:\Users\zaki>
※ 上記はMinishiftがすでにインストール済みの環境であり、設定が共通($HOME/.kubeを見ている)のため、現在稼働していない192.168.99.103を見ようとしてエラーになっている)
Kubernetesクラスタの起動
minikube startで起動(初回はVM作成)が行われる。
ただし、ハイパーバイザのデフォルトがHyper-V…と思ったけど、Minishiftと違って最初からVirtualBoxっぽい。
明示的に指定するには--vm-driverオプションでvirtualboxを指定する。
詳細はminishift start --helpで確認できる。
PS C:\Users\zaki> minikube start --help
Starts a local kubernetes cluster using VM. This command
assumes you have already installed one of the VM drivers: virtualbox/parallels/vmwarefusion/kvm/xhyve/hyperv.
[...]
--vm-driver string VM driver is one of: [virtualbox parallels vmwarefusion kvm xhyve hyperv hyperkit kvm2 vmware none] (default "virtualbox")
というわけで起動。
PS C:\Users\zaki> minikube start --vm-driver virtualbox
o minikube v0.35.0 on windows (amd64)
> Creating virtualbox VM (CPUs=2, Memory=2048MB, Disk=20000MB) ...
@ Downloading Minikube ISO ...
20.94 MB / 184.42 MB [====>---------------------------------------] 11.35% 17s
初回のVM作成処理が始まると、VirtualBox上にクラスタ用のVMが作成される
PS C:\Users\zaki> minikube start --vm-driver virtualbox
o minikube v0.35.0 on windows (amd64)
> Creating virtualbox VM (CPUs=2, Memory=2048MB, Disk=20000MB) ...
@ Downloading Minikube ISO ...
184.42 MB / 184.42 MB [============================================] 100.00% 0s
- "minikube" IP address is 192.168.99.100
- Configuring Docker as the container runtime ...
- Preparing Kubernetes environment ...
@ Downloading kubelet v1.13.4
@ Downloading kubeadm v1.13.4
- Pulling images required by Kubernetes v1.13.4 ...
- Launching Kubernetes v1.13.4 using kubeadm ...
: Waiting for pods: apiserver proxy etcd scheduler controller addon-manager dns
- Configuring cluster permissions ...
- Verifying component health .....
+ kubectl is now configured to use "minikube"
= Done! Thank you for using minikube!
PS C:\Users\zaki>
Minishiftより簡素なのか、起動も早い…
起動完了したら、kubectlの出番
バージョン
PS C:\Users\zaki> kubectl version
Client Version: version.Info{Major:"1", Minor:"13", GitVersion:"v1.13.0", GitCommit:"ddf47ac13c1a9483ea035a79cd7c10005ff21a6d", GitTreeState:"clean", BuildDate:"2018-12-03T21:04:45Z", GoVersion:"go1.11.2", Compiler:"gc", Platform:"windows/amd64"}
Server Version: version.Info{Major:"1", Minor:"13", GitVersion:"v1.13.4", GitCommit:"c27b913fddd1a6c480c229191a087698aa92f0b1", GitTreeState:"clean", BuildDate:"2019-02-28T13:30:26Z", GoVersion:"go1.11.5", Compiler:"gc", Platform:"linux/amd64"}
PS C:\Users\zaki>
さっきは接続エラーになっていたサーバに接続できて、クラスタの状態を取得できている
クラスタ情報
PS C:\Users\zaki> kubectl cluster-info
Kubernetes master is running at https://192.168.99.100:8443
KubeDNS is running at https://192.168.99.100:8443/api/v1/namespaces/kube-system/services/kube-dns:dns/proxy
To further debug and diagnose cluster problems, use 'kubectl cluster-info dump'.
PS C:\Users\zaki>
Kubernatesクラスタの停止
stopを引数に実行。VMが停止する。
PS C:\Users\zaki> minikube stop
: Stopping "minikube" in virtualbox ...
- "minikube" stopped.
PS C:\Users\zaki>
インストール直後のクラスタの状態
node
PS C:\Users\zaki> kubectl get node
NAME STATUS ROLES AGE VERSION
minikube Ready master 5m33s v1.13.4
namespace
PS C:\Users\zaki> kubectl get namespace
NAME STATUS AGE
default Active 32m
kube-public Active 31m
kube-system Active 32m
oc project <namespace>に相当するコマンドはないっぽい。。
all
PS C:\Users\zaki> kubectl get all --all-namespaces -o wide
NAMESPACE NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
kube-system pod/coredns-86c58d9df4-b8p67 1/1 Running 0 19m 172.17.0.2 minikube <none> <none>
kube-system pod/coredns-86c58d9df4-fzfx4 1/1 Running 0 19m 172.17.0.3 minikube <none> <none>
kube-system pod/etcd-minikube 1/1 Running 0 18m 10.0.2.15 minikube <none> <none>
kube-system pod/kube-addon-manager-minikube 1/1 Running 0 18m 10.0.2.15 minikube <none> <none>
kube-system pod/kube-apiserver-minikube 1/1 Running 0 18m 10.0.2.15 minikube <none> <none>
kube-system pod/kube-controller-manager-minikube 1/1 Running 0 18m 10.0.2.15 minikube <none> <none>
kube-system pod/kube-proxy-6647b 1/1 Running 0 19m 10.0.2.15 minikube <none> <none>
kube-system pod/kube-scheduler-minikube 1/1 Running 0 18m 10.0.2.15 minikube <none> <none>
kube-system pod/kubernetes-dashboard-ccc79bfc9-ksl8g 1/1 Running 0 3m3s 172.17.0.4 minikube <none> <none>
kube-system pod/storage-provisioner 1/1 Running 0 19m 10.0.2.15 minikube <none> <none>
NAMESPACE NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
default service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 19m <none>
kube-system service/kube-dns ClusterIP 10.96.0.10 <none> 53/UDP,53/TCP 19m k8s-app=kube-dns
kube-system service/kubernetes-dashboard ClusterIP 10.109.210.17 <none> 80/TCP 3m3s app=kubernetes-dashboard
NAMESPACE NAME DESIRED CURRENT READY UP-TO-DATE AVAILABLE NODE SELECTOR AGE CONTAINERS IMAGES SELECTOR
kube-system daemonset.apps/kube-proxy 1 1 1 1 1 <none> 19m kube-proxy k8s.gcr.io/kube-proxy:v1.13.4 k8s-app=kube-proxy
NAMESPACE NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
kube-system deployment.apps/coredns 2/2 2 2 19m coredns k8s.gcr.io/coredns:1.2.6 k8s-app=kube-dns
kube-system deployment.apps/kubernetes-dashboard 1/1 1 1 3m3s kubernetes-dashboard k8s.gcr.io/kubernetes-dashboard-amd64:v1.10.1 addonmanager.kubernetes.io/mode=Reconcile,app=kubernetes-dashboard,version=v1.10.1
NAMESPACE NAME DESIRED CURRENT READY AGE CONTAINERS IMAGES SELECTOR
kube-system replicaset.apps/coredns-86c58d9df4 2 2 2 19m coredns k8s.gcr.io/coredns:1.2.6 k8s-app=kube-dns,pod-template-hash=86c58d9df4
kube-system replicaset.apps/kubernetes-dashboard-ccc79bfc9 1 1 1 3m3s kubernetes-dashboard k8s.gcr.io/kubernetes-dashboard-amd64:v1.10.1 addonmanager.kubernetes.io/mode=Reconcile,app=kubernetes-dashboard,pod-template-hash=ccc79bfc9,version=v1.10.1
PS C:\Users\zaki>
dashboard
minikube dashboardを実行することで起動するので、ブラウザでアクセスすれば見れる。
PS C:\Users\zaki> minikube dashboard
- Enabling dashboard ...
- Verifying dashboard health ...
- Launching proxy ...
- Verifying proxy health ...
- Opening http://127.0.0.1:52301/api/v1/namespaces/kube-system/services/http:kubernetes-dashboard:/proxy/ in your default browser...
echoserverチュートリアル
Install Minikube - Kubernetesでの構築が終わったら、最後に What's next という項目があるので、その内容をいくつかやってみる
Running Kubernetes Locally via Minikube - Kubernetes
Podの実行
see: Quickstart
kubectl run hello-minikube --image=k8s.gcr.io/echoserver:1.10 --port=8080
PS C:\Users\zaki> kubectl run hello-minikube --image=k8s.gcr.io/echoserver:1.10 --port=8080
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/hello-minikube created
PS C:\Users\zaki>
PS C:\Users\zaki> kubectl get all
NAME READY STATUS RESTARTS AGE
pod/hello-minikube-6fd785d459-2xq6j 0/1 ContainerCreating 0 14s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 35m
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/hello-minikube 0/1 1 0 14s
NAME DESIRED CURRENT READY AGE
replicaset.apps/hello-minikube-6fd785d459 1 1 0 14s
hello-minikubeという名前で、k8s.gcr.io/echoserver:1.10イメージベースでDeployment/ReplicaSet/Podが作成された。
(上のログのPodの状態はREADYの値が0/1になっており、STATUSもContainerCreating(コンテナ作成中)となっていて、起動処理中の状態)
時間がたてば
PS C:\Users\zaki> kubectl get pod
NAME READY STATUS RESTARTS AGE
hello-minikube-6fd785d459-2xq6j 1/1 Running 0 5m25s
PS C:\Users\zaki>
Runningになった (Podが実行中状態)
Service作成
PS C:\Users\zaki> kubectl expose deployment hello-minikube --type=NodePort
service/hello-minikube exposed
PS C:\Users\zaki> kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
hello-minikube NodePort 10.108.176.189 <none> 8080:30198/TCP 7s
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 37m
Serviceが作成され、外部からアクセスする準備ができた。
アクセスのためのURLを確認するにはminikube service listを実行すると一覧が見れる
PS C:\Users\zaki> minikube service list
|-------------|----------------------|-----------------------------|
| NAMESPACE | NAME | URL |
|-------------|----------------------|-----------------------------|
| default | hello-minikube | http://192.168.99.100:30198 |
| default | kubernetes | No node port |
| kube-system | kube-dns | No node port |
| kube-system | kubernetes-dashboard | No node port |
|-------------|----------------------|-----------------------------|
PS C:\Users\zaki>
http://192.168.99.100:30198にアクセスすれば、Podで動作しているechoserverにアクセスできることがわかる。
PS C:\Users\zaki> $resp =Invoke-WebRequest http://192.168.99.100:30198
PS C:\Users\zaki> $resp.Content
Hostname: hello-minikube-6fd785d459-2xq6j
Pod Information:
-no pod information available-
Server values:
server_version=nginx: 1.13.3 - lua: 10008
Request Information:
client_address=172.17.0.1
method=GET
real path=/
query=
request_version=1.1
request_scheme=http
request_uri=http://192.168.99.100:8080/
Request Headers:
host=192.168.99.100:30198
user-agent=Mozilla/5.0 (Windows NT; Windows NT 10.0; ja-JP) WindowsPowerShell/5.1.17763.316
Request Body:
-no body in request-
PS C:\Users\zaki>
dashboard
echoserverのPodが動作している状態でdashboardを見ると、こんな感じ
各リソースの詳細(おまけのメモ)
Deployment
PS C:\Users\zaki> kubectl get deploy hello-minikube -o yaml
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
annotations:
deployment.kubernetes.io/revision: "1"
creationTimestamp: "2019-03-19T13:26:08Z"
generation: 1
labels:
run: hello-minikube
name: hello-minikube
namespace: default
resourceVersion: "2948"
selfLink: /apis/extensions/v1beta1/namespaces/default/deployments/hello-minikube
uid: 8e6ef4dd-4a4a-11e9-9d31-080027b9884e
spec:
progressDeadlineSeconds: 600
replicas: 1
revisionHistoryLimit: 10
selector:
matchLabels:
run: hello-minikube
strategy:
rollingUpdate:
maxSurge: 25%
maxUnavailable: 25%
type: RollingUpdate
template:
metadata:
creationTimestamp: null
labels:
run: hello-minikube
spec:
containers:
- image: k8s.gcr.io/echoserver:1.10
imagePullPolicy: IfNotPresent
name: hello-minikube
ports:
- containerPort: 8080
protocol: TCP
resources: {}
terminationMessagePath: /dev/termination-log
terminationMessagePolicy: File
dnsPolicy: ClusterFirst
restartPolicy: Always
schedulerName: default-scheduler
securityContext: {}
terminationGracePeriodSeconds: 30
status:
availableReplicas: 1
conditions:
- lastTransitionTime: "2019-03-19T13:26:32Z"
lastUpdateTime: "2019-03-19T13:26:32Z"
message: Deployment has minimum availability.
reason: MinimumReplicasAvailable
status: "True"
type: Available
- lastTransitionTime: "2019-03-19T13:26:08Z"
lastUpdateTime: "2019-03-19T13:26:32Z"
message: ReplicaSet "hello-minikube-6fd785d459" has successfully progressed.
reason: NewReplicaSetAvailable
status: "True"
type: Progressing
observedGeneration: 1
readyReplicas: 1
replicas: 1
updatedReplicas: 1
ReplicaSet
PS C:\Users\zaki> kubectl get rs hello-minikube-6fd785d459 -o yaml
apiVersion: extensions/v1beta1
kind: ReplicaSet
metadata:
annotations:
deployment.kubernetes.io/desired-replicas: "1"
deployment.kubernetes.io/max-replicas: "2"
deployment.kubernetes.io/revision: "1"
creationTimestamp: "2019-03-19T13:26:08Z"
generation: 1
labels:
pod-template-hash: 6fd785d459
run: hello-minikube
name: hello-minikube-6fd785d459
namespace: default
ownerReferences:
- apiVersion: apps/v1
blockOwnerDeletion: true
controller: true
kind: Deployment
name: hello-minikube
uid: 8e6ef4dd-4a4a-11e9-9d31-080027b9884e
resourceVersion: "2947"
selfLink: /apis/extensions/v1beta1/namespaces/default/replicasets/hello-minikube-6fd785d459
uid: 8e71147d-4a4a-11e9-9d31-080027b9884e
spec:
replicas: 1
selector:
matchLabels:
pod-template-hash: 6fd785d459
run: hello-minikube
template:
metadata:
creationTimestamp: null
labels:
pod-template-hash: 6fd785d459
run: hello-minikube
spec:
containers:
- image: k8s.gcr.io/echoserver:1.10
imagePullPolicy: IfNotPresent
name: hello-minikube
ports:
- containerPort: 8080
protocol: TCP
resources: {}
terminationMessagePath: /dev/termination-log
terminationMessagePolicy: File
dnsPolicy: ClusterFirst
restartPolicy: Always
schedulerName: default-scheduler
securityContext: {}
terminationGracePeriodSeconds: 30
status:
availableReplicas: 1
fullyLabeledReplicas: 1
observedGeneration: 1
readyReplicas: 1
replicas: 1
Pod
PS C:\Users\zaki> kubectl get pod hello-minikube-6fd785d459-2xq6j -o yaml
apiVersion: v1
kind: Pod
metadata:
creationTimestamp: "2019-03-19T13:26:08Z"
generateName: hello-minikube-6fd785d459-
labels:
pod-template-hash: 6fd785d459
run: hello-minikube
name: hello-minikube-6fd785d459-2xq6j
namespace: default
ownerReferences:
- apiVersion: apps/v1
blockOwnerDeletion: true
controller: true
kind: ReplicaSet
name: hello-minikube-6fd785d459
uid: 8e71147d-4a4a-11e9-9d31-080027b9884e
resourceVersion: "2946"
selfLink: /api/v1/namespaces/default/pods/hello-minikube-6fd785d459-2xq6j
uid: 8e743dd5-4a4a-11e9-9d31-080027b9884e
spec:
containers:
- image: k8s.gcr.io/echoserver:1.10
imagePullPolicy: IfNotPresent
name: hello-minikube
ports:
- containerPort: 8080
protocol: TCP
resources: {}
terminationMessagePath: /dev/termination-log
terminationMessagePolicy: File
volumeMounts:
- mountPath: /var/run/secrets/kubernetes.io/serviceaccount
name: default-token-qr2gn
readOnly: true
dnsPolicy: ClusterFirst
enableServiceLinks: true
nodeName: minikube
priority: 0
restartPolicy: Always
schedulerName: default-scheduler
securityContext: {}
serviceAccount: default
serviceAccountName: default
terminationGracePeriodSeconds: 30
tolerations:
- effect: NoExecute
key: node.kubernetes.io/not-ready
operator: Exists
tolerationSeconds: 300
- effect: NoExecute
key: node.kubernetes.io/unreachable
operator: Exists
tolerationSeconds: 300
volumes:
- name: default-token-qr2gn
secret:
defaultMode: 420
secretName: default-token-qr2gn
status:
conditions:
- lastProbeTime: null
lastTransitionTime: "2019-03-19T13:26:08Z"
status: "True"
type: Initialized
- lastProbeTime: null
lastTransitionTime: "2019-03-19T13:26:32Z"
status: "True"
type: Ready
- lastProbeTime: null
lastTransitionTime: "2019-03-19T13:26:32Z"
status: "True"
type: ContainersReady
- lastProbeTime: null
lastTransitionTime: "2019-03-19T13:26:08Z"
status: "True"
type: PodScheduled
containerStatuses:
- containerID: docker://1bf516296ef57c298d753510d7edd54c9c009055a5d89f7475ddfb12e298905d
image: k8s.gcr.io/echoserver:1.10
imageID: docker-pullable://k8s.gcr.io/echoserver@sha256:cb5c1bddd1b5665e1867a7fa1b5fa843a47ee433bbb75d4293888b71def53229
lastState: {}
name: hello-minikube
ready: true
restartCount: 0
state:
running:
startedAt: "2019-03-19T13:26:32Z"
hostIP: 10.0.2.15
phase: Running
podIP: 172.17.0.5
qosClass: BestEffort
startTime: "2019-03-19T13:26:08Z"