kubernetes學習筆記（二）：bashborad安裝配置
官方推薦方法：
連接：https://kubernetes.io/docs/tasks/access-application-cluster/web-ui-dashboard/
運行推薦yaml：
kubectl create -f https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml但是因為國內無法上google的原因，此辦法一般都會報錯。推薦以下辦法：
daocloude鏡像地址：https://dashboard.daocloud.io/packages
1、編寫yaml文件
dashboard.yaml
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
# Keep the name in sync with image version and
# gce/coreos/kube-manifests/addons/dashboard counterparts
name: kubernetes-dashboard-latest
namespace: kube-system
spec:
replicas: 1
template:
metadata:
labels:
k8s-app: kubernetes-dashboard
version: latest
kubernetes.io/cluster-service: "true"
spec:
containers:
- name: kubernetes-dashboard
image: daocloud.io/gfkchinanetquest/kubernetes-dashboard-amd64:v1.5.1
#這裏使用daoclod的鏡像，默認鏡像為gcr.io/google_containers/kubernetes-dashboard-amd64:v1.5.1
resources:
# keep request = limit to keep this container in guaranteed class
limits:
cpu: 100m
memory: 50Mi
requests:
cpu: 100m
memory: 50Mi
ports:
- containerPort: 9090
args:
- --apiserver-host=http://192.168.50.131:8080 #這裏修改為自己環境master的地址
dashboardsvc.yaml
apiVersion: v1
kind: Service
metadata:
name: kubernetes-dashboard
namespace: kube-system
labels:
k8s-app: kubernetes-dashboard
kubernetes.io/cluster-service: "true"
spec:
selector:
k8s-app: kubernetes-dashboard
ports:
- port: 80
targetPort: 9090
2、創建depolyment和service
正常情況下創建depolyment和service，
kubectl create -f dashboard.yaml
kubectl create -f dashboardsvc.yaml
3、驗證
master上執行
[root@test03 pods]# kubectl get deploy --namespace=kube-system
NAME DESIRED CURRENT UP-TO-DATE AVAILABLE AGE
kubernetes-dashboard-latest 1 1 1 1 45m
[root@test03 pods]# kubectl get svc --namespace=kube-system
NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes-dashboard 10.254.211.210 <none> 80/TCP 45m
[root@test03 pods]# kubectl get pod -o wide --all-namespaces
NAMESPACE NAME READY STATUS RESTARTS AGE IP NODE
default nginx01 1/1 Running 0 8d 172.30.42.2 node01
default nginx03 1/1 Running 0 10h 172.30.53.2 node02
kube-system kubernetes-dashboard-latest-713129511-8p8gn 1/1 Running 0 46m 172.30.53.3 node02
通過頁面訪問：http://192.168.50.131:8080/ui
ps:會跳轉到http://192.168.50.131:8080/api/v1/proxy/namespaces/kube-system/services/kubernetes-dashboard/#/workload?namespace=default
其實最終訪問的是：http://172.30.53.3:9090/ 及node上的pod
4、遇到的問題
就可以通過頁面http://192.168.50.131:8080/ui就可以訪問bashborad了。但是這裏有幾個坑
（1）國內無法訪問gcr.io的鏡像，所以在dashboard.yaml中我們使用daoclod的鏡像，可以現在node節點中docker pull一下，確認是否可以拉取鏡像。
我的環境不是很穩定，其中一個node02拉去成功，第二個node01拉取失敗，並且創建的pod正好在失敗的節點上。
[root@test03 pods]# kubectl get pod -o wide --all-namespaces
NAMESPACE NAME READY STATUS RESTARTS AGE IP NODE
default nginx01 1/1 Running 0 7d 172.30.42.2 node01
default nginx03 1/1 Running 0 3h 172.30.53.2 node02
kube-system kubernetes-dashboard-latest-2290711670-q5kzx 0/1 ImagePullBackOff 0 34m 172.30.42.3 node01
表示創建pod失敗，使用kubectl describe pods --namespace=kube-system，查看報錯日誌，一般都是鏡像拉取失敗
現在需要再node01中拉取鏡像，可以通過node02的鏡像load即可。
node02：
[root@test01 ~]# docker images REPOSITORY TAG IMAGE ID CREATED SIZE docker.io/nginx latest e548f1a579cf 3 weeks ago 108.6 MB registry.access.redhat.com/rhel7/pod-infrastructure latest 99965fb98423 5 months ago 208.6 MB daocloud.io/gfkchinanetquest/kubernetes-dashboard-amd64 v1.5.1 1180413103fd 14 months ago 103.6 MB ansible/centos7-ansible-tag latest 688353a31fde 15 months ago 447.2 MB ansible/centos7-ansible latest 688353a31fde 15 months ago 447.2 MB docker.io/kubernetes/pause latest f9d5de079539 3 years ago 239.8 kB gcr.io/google_containers/pause 2.0 f9d5de079539 3 years ago 239.8 kB [root@test01 ~]# docker save daocloud.io/gfkchinanetquest/kubernetes-dashboard-amd64:v1.5.1 > bashborad.tar [root@test01 ~]# ll total 160592 -rw-------. 1 root root 1026 Feb 5 23:08 anaconda-ks.cfg -rw-r--r--. 1 root root 103781888 Mar 15 00:20 bashborad.tar -r--r--r--. 1 root root 60654199 Aug 27 2013 VMwareTools-9.6.0-1294478.tar.gz
scp bashborad.tar到node01 執行load即可，docker image查看，發現鏡像已經導入
docker load < dashboard.tar
此時node上鏡像已經都已經拉取成功，需要銷毀重新創建deployment和service
master上執行
kubectl delete deployment kubernetes-dashboard-latest --namespace=kube-system kubectl delete svc kubernetes-dashboard --namespace=kube-system 創建： kubectl create -f bashborad.yaml kubectl create -f bashboradsvc.yaml
2、flannel網路問題，安裝成功，訪問頁面失敗
訪問http://192.168.50.131:8080/ui,沒有反應
訪問：http://192.168.50.131:8080/api/v1/proxy/namespaces/kube-system/services/kubernetes-dashboard/#/workload?namespace=default
報錯如下：
Error: ‘dial tcp 172.30.53.3:9090: getsockopt: connection timed out‘ Trying to reach: ‘http://172.30.53.3:9090/‘
根據提示能夠知道192.168.50.131無法訪問172.30.53.3:9090。ifconfig查看master上的網絡，發現沒有flanne網絡，可能之前忘記重啟了，systemctl restart flanneld
flannel.1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1450
inet 172.30.10.0 netmask 255.255.255.255 broadcast 0.0.0.0
inet6 fe80::e051:bfff:fefe:d009 prefixlen 64 scopeid 0x20<link>
ether e2:51:bf:fe:d0:09 txqueuelen 0 (Ethernet)
RX packets 1249 bytes 1625343 (1.5 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 481 bytes 42378 (41.3 KiB)
TX errors 0 dropped 10 overruns 0 carrier 0 collisions 0
3、node節點上鏡像pull成功，但是還是安裝失敗
dashboard.yaml中
daocloud.io/gfkchinanetquest/kubernetes-dashboard-amd64:v1.5.1
沒有選擇版本，如果為 daocloud.io/gfkchinanetquest/kubernetes-dashboard-amd64，則表示拉去lastest版本，即
daocloud.io/gfkchinanetquest/kubernetes-dashboard-amd64:lastest
但是因為我們是離線load的，並沒有lastest版本，所以會報錯。
4、不修改dashboard.yaml內容的方法
load鏡像後，tag鏡像為
gcr.io/google_containers/kubernetes-dashboard-amd64:v1.5.1即可。（後續補充）
kubernetes學習筆記（二）：bashborad安裝配置