Kubenetes 部署 Dashboard
Kubenestes Dashboard 是提供 Kubernetes信息可视化的 Web 插件
部署
kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0-beta1/aio/deploy/recommended.yaml
配置
修改为通过 NodePort 访问
kubectl -n kubernetes-dashboard edit service kubernetes-dashboard
在 ports下面添加nodePort: 32576，将 clusterIp改为NodePort
spec:
clusterIP: 10.104.3.252
externalTrafficPolicy: Cluster
ports:
- nodePort: 32576
port: 443
protocol: TCP
targetPort: 8443
selector:
k8s-app: kubernetes-dashboard
sessionAffinity: None
type: NodePort
此时可以通过节点 IP 和端口https://192.168.0.110:32576/访问到 Dashboard(Chrome 可能会提示证书错误,无法访问,Fix)
创建 ServiceAccount
vi admin-role.yaml
输入以下内容
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: admin
annotations:
rbac.authorization.kubernetes.io/autoupdate: "true"
roleRef:
kind: ClusterRole
name: cluster-admin
apiGroup: rbac.authorization.k8s.io
subjects:
- kind: ServiceAccount
name: admin
namespace: kubernetes-dashboard
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: admin
namespace: kubernetes-dashboard
labels:
kubernetes.io/cluster-service: "true"
addonmanager.kubernetes.io/mode: Reconcile
kubectl apply -f admin-role.yaml
获取 Token
执行：
kubectl -n kubernetes-dashboard get secret|grep admin-token
admin-token-r8b4b kubernetes.io/service-account-token 3 48m
kubernetes-dashboard-admin-token-qlnhp kubernetes.io/service-account-token 3 60m
执行：
kubectl -n kubernetes-dashboard describe secret admin-token-r8b4b
Name: admin-token-r8b4b
Namespace: kubernetes-dashboard
Labels: <none>
Annotations: kubernetes.io/service-account.name: admin
kubernetes.io/service-account.uid: 03a2bca0-b6c0-4cde-93aa-c4a6cd70dfdb
Type: kubernetes.io/service-account-token
Data
====
ca.crt: 1025 bytes
namespace: 20 bytes
token: eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJrdWJlcm5ldGVzLWRhc2hib2FyZCIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VjcmV0Lm5hbWUiOiJhZG1pbi10b2tlbi1yOGI0YiIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50Lm5hbWUiOiJhZG1pbiIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50LnVpZCI6IjAzYTJiY2EwLWI2YzAtNGNkZS05M2FhLWM0YTZjZDcwZGZkYiIsInN1YiI6InN5c3RlbTpzZXJ2aWNlYWNjb3VudDprdWJlcm5ldGVzLWRhc2hib2FyZDphZG1pbiJ9.g_dtJjhbLVfJRcdhlyYH-ekn08Dv3_Ok9oMZ7o0jU0Ri90sIhaANaprVlGK7QiKzIkz_BNT1Hw_reAseoOy7smFriKhn4a4wPMO0Ir1aJPavDdoVIEhBDHHzrukXl3mVO92WgkBkAMIo8HoVve-1pj9QVtT7hu_e8GXifyLu1v6s26lMbVouG8cPD4hzM2grRfhCt7qjioP3Gs6khtmHysu_uCBNW63HvuwzMBRS-lSr1ewWld4QnrvgqJ-IfLqAcjHjysNR26Xi9IBAswkq0E-1qSgIyduALITXx9FK9RqNBOTZ33OeDBCE-OYqmlIItDuYl4qRaksV3mccL4RVWA
将获取到的 Token 输入到 Dashboard 的输入框中，登录即可
遇到的问题
1. 访问页面提示ServiceUnavailable
{
"kind": "Status",
"apiVersion": "v1",
"metadata": {
},
"status": "Failure",
"message": "no endpoints available for service \"https:kubernetes-dashboard:\"",
"reason": "ServiceUnavailable",
"code": 503
}
查看 Dashboard Pod 的状态
kubectl get pods -n kube-system | grep dashboard
kubernetes-dashboard-77fd78f978-zqbs4 0/1 ImagePullBackOff 0 115m
查看 Pod 详细信息
kubectl -n kube-system describe pod kubernetes-dashboard-77fd78f978-zqbs4
Name: kubernetes-dashboard-77fd78f978-zqbs4
Namespace: kube-system
Priority: 0
PriorityClassName: <none>
Node: ubuntu/192.168.111.129
Start Time: Tue, 16 Oct 2018 09:50:14 +0000
Labels: k8s-app=kubernetes-dashboard
pod-template-hash=77fd78f978
Annotations: <none>
Status: Pending
IP: 10.32.0.4
Controlled By: ReplicaSet/kubernetes-dashboard-77fd78f978
Containers:
kubernetes-dashboard:
Container ID:
Image: k8s.gcr.io/kubernetes-dashboard-amd64:v1.10.0
Image ID:
Port: 8443/TCP
Host Port: 0/TCP
Args:
--auto-generate-certificates
State: Waiting
Reason: ImagePullBackOff
Ready: False
Restart Count: 0
Liveness: http-get https://:8443/ delay=30s timeout=30s period=10s #success=1 #failure=3
Environment: <none>
Mounts:
/certs from kubernetes-dashboard-certs (rw)
/tmp from tmp-volume (rw)
/var/run/secrets/kubernetes.io/serviceaccount from kubernetes-dashboard-token-7skvp (ro)
Conditions:
Type Status
Initialized True
Ready False
ContainersReady False
PodScheduled True
Volumes:
kubernetes-dashboard-certs:
Type: Secret (a volume populated by a Secret)
SecretName: kubernetes-dashboard-certs
Optional: false
tmp-volume:
Type: EmptyDir (a temporary directory that shares a pod's lifetime)
Medium:
kubernetes-dashboard-token-7skvp:
Type: Secret (a volume populated by a Secret)
SecretName: kubernetes-dashboard-token-7skvp
Optional: false
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node-role.kubernetes.io/master:NoSchedule
node.kubernetes.io/not-ready:NoExecute for 300s
node.kubernetes.io/unreachable:NoExecute for 300s
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Warning Failed 9m17s (x458 over 119m) kubelet, ubuntu Error: ImagePullBackOff
Normal BackOff 4m14s (x479 over 119m) kubelet, ubuntu Back-off pulling image "k8s.gcr.io/kubernetes-dashboard-amd64:v1.10.0"
最后一行可以看到在拉取镜像的时候失败了；可以先拉取镜像再启动，这里有两种解决办法：
# 1. 如果网络可以拉取到镜像，直接手动拉取即可
docker pull k8s.gcr.io/kubernetes-dashboard-amd64:v1.10.0
# 2. 如果拉取不到，尝试从其他镜像源拉取重新打标签
docker pull registry.cn-hangzhou.aliyuncs.com/google_containers/kubernetes-dashboard-amd64:v1.10.0
docker tag registry.cn-hangzhou.aliyuncs.com/google_containers/kubernetes-dashboard-amd64:v1.10.0 k8s.gcr.io/kubernetes-dashboard-amd64:v1.10.0
docker rmi registry.cn-hangzhou.aliyuncs.com/google_containers/kubernetes-dashboard-amd64:v1.10.0
拉取到镜像之后等待一会儿，Kubernetes 会自动创建新的 Pod；或者也可以删除 Dashboard 所有资源重新创建：
kubectl delete -f https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml
2. 重启后使用 kubectl 提示 The connection to the server 192.168.111.129:6443 was refused - did you specify the right host or port?
重启Ubuntu 后，访问Dashboard timeout，通过kubectl get pods -n kube-system查看 Pod 状态，提示
The connection to the server 192.168.111.129:6443 was refused - did you specify the right host or port?
以为是配置的问题，但是参考 https://github.com/kubernetes/kubernetes/issues/50295#issuecomment-376603921，尝试后依然无法解决；最后尝试使用kubeadm init重新创建，提示
running with swap on is not supported. Please disable swap
因为 Swap 导致Kubenetes 没有成功启动，执行关闭 swap，重新启动后解决问题
sudo swapoff -a
sudo chown $(id -u):$(id -g) $HOME/.kube/config