I am new to Rancher and containers in general. While setting up Kubernetes cluster using Rancher, i’m facing problem while accessing Kubernetes dashboard.
rancher/server: 1.6.6
Single node Rancher server + External MySQL + 3 agent nodes
Infrastructure Stack versions:
healthcheck: v0.3.1
ipsec: net:v0.11.5
network-services: metadata:v0.9.2 / network-manager:v0.7.7
scheduler: k8s:v1.7.2-rancher5
kubernetes (if applicable): kubernetes-agent:v0.6.3
# docker info
Containers: 1
Running: 1
Paused: 0
Stopped: 0
Images: 1
Server Version: 17.03.1-ce
Storage Driver: overlay
Backing Filesystem: extfs
Supports d_type: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
Volume: local
Network: bridge host macvlan null overlay
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Init Binary: docker-init
containerd version: 4ab9917febca54791c5f071a9d1f404867857fcc
runc version: 54296cf40ad8143b62dbcaa1d90e520a2136ddfe
init version: 949e6fa
Security Options:
seccomp
Profile: default
Kernel Version: 4.9.34-rancher
Operating System: RancherOS v1.0.3
OSType: linux
Architecture: x86_64
CPUs: 2
Total Memory: 7.798 GiB
Name: ch7radod1
ID: IUNS:4WT2:Y3TV:2RI4:FZQO:4HYD:YSNN:6DPT:HMQ6:S2SI:OPGH:TX4Y
Docker Root Dir: /var/lib/docker
Debug Mode (client): false
Debug Mode (server): false
Http Proxy: http://proxy.ch.abc.net:8080
Https Proxy: http://proxy.ch.abc.net:8080
No Proxy: localhost,.xyz.net,abc.net
Registry: https://index.docker.io/v1/
Insecure Registries:
127.0.0.0/8
Live Restore Enabled: falseAccessing UI URL http://10.216.30.10/r/projects/1a6633/kubernetes-dashboard:9090/# shows “Service unavailable”
If i use the CLI section from the UI, i get the following:
> kubectl get nodes
NAME STATUS AGE VERSION
ch7radod3 Ready 1d v1.7.2
ch7radod4 Ready 5d v1.7.2
ch7radod1 Ready 1d v1.7.2
> kubectl get pods --all-namespaces
NAMESPACE NAME READY STATUS RESTARTS AGE
kube-system heapster-4285517626-4njc2 0/1 ContainerCreating 0 5d
kube-system kube-dns-3942128195-ft56n 0/3 ContainerCreating 0 19d
kube-system kube-dns-646531078-z5lzs 0/3 ContainerCreating 0 5d
kube-system kubernetes-dashboard-716739405-lpj38 0/1 ContainerCreating 0 5d
kube-system monitoring-grafana-3552275057-qn0zf 0/1 ContainerCreating 0 5d
kube-system monitoring-influxdb-4110454889-79pvk 0/1 ContainerCreating 0 5d
kube-system tiller-deploy-737598192-f9gcl 0/1 ContainerCreating 0 5dThe setup uses private registry (Artifactory). I checked Artifactory and i could see several images present related to Docker. I was going through private registry section and i also saw this file. In case this file is required, where exactly do i keep it so that Rancher can fetch it and configure the Kubernetes dashboard?
UPDATE:
$ sudo ros engine switch docker-1.12.6
> ERRO[0031] Failed to load https://raw.githubusercontent.com/rancher/os-services/v1.0.3/index.yml: Get https://raw.githubusercontent.com/rancher/os-services/v1.0.3/index.yml: Proxy Authentication Required
> FATA[0031] docker-1.12.6 is not a valid engineI thought may be it’s due to NGINX so i stopped the NGINX container but i am still getting the above error. Earlier i have tried the same command on this Rancher server and it used to work fine. It’s working fine on agent nodes although they are already having 1.12.6 configured.
UPDATE 2:
> kubectl -n kube-system get po
NAME READY STATUS RESTARTS AGE
heapster-4285517626-4njc2 1/1 Running 0 12d
kube-dns-2588877561-26993 0/3 ImagePullBackOff 0 5h
kube-dns-646531078-z5lzs 0/3 ContainerCreating 0 12d
kubernetes-dashboard-716739405-zq3s9 0/1 CrashLoopBackOff 67 5h
monitoring-grafana-3552275057-qn0zf 1/1 Running 0 12d
monitoring-influxdb-4110454889-79pvk 1/1 Running 0 12d
tiller-deploy-737598192-f9gcl 0/1 CrashLoopBackOff 72 12dBased on @ivan.sim's suggestion, i posted 'UPDATE 2'. This started me finally to look in the right direction. I then started looking for CrashLoopBackOff error online and came across this link and tried the following command (using CLI option from Rancher console), which was actually quite similar to what @ivan.sim suggested above but this helped me with the node where the dashboard process was running:
> kubectl get pods -a -o wide --all-namespaces
NAMESPACE NAME READY STATUS RESTARTS AGE IP NODE
kube-system heapster-4285517626-4njc2 1/1 Running 0 12d 10.42.224.157 radod4
kube-system kube-dns-2588877561-26993 0/3 ImagePullBackOff 0 5h <none> radod1
kube-system kube-dns-646531078-z5lzs 0/3 ContainerCreating 0 12d <none> radod4
kube-system kubernetes-dashboard-716739405-zq3s9 0/1 Error 70 5h 10.42.218.11 radod1
kube-system monitoring-grafana-3552275057-qn0zf 1/1 Running 0 12d 10.42.202.44 radod4
kube-system monitoring-influxdb-4110454889-79pvk 1/1 Running 0 12d 10.42.111.171 radod4
kube-system tiller-deploy-737598192-f9gcl 0/1 CrashLoopBackOff 76 12d 10.42.213.24 radod4Then i went to the host where the process was executing and tried the following command:
[rancher@radod1 ~]$
[rancher@radod1 ~]$ docker ps -a | grep dash
282334b0ed38 gcr.io/google_containers/kubernetes-dashboard-amd64@sha256:b537ce8988510607e95b8d40ac9824523b1f9029e6f9f90e9fccc663c355cf5d "/dashboard --insecur" About a minute ago Exited (1) 55 seconds ago k8s_kubernetes-dashboard_kubernetes-dashboard-716739405-zq3s9_kube-system_7b0afda7-8271-11e7-ae86-021bfe69c163_72
99836d7824fd gcr.io/google_containers/pause-amd64:3.0 "/pause" 5 hours ago Up 5 hours k8s_POD_kubernetes-dashboard-716739405-zq3s9_kube-system_7b0afda7-8271-11e7-ae86-021bfe69c163_1
[rancher@radod1 ~]$
[rancher@radod1 ~]$
[rancher@radod1 ~]$ docker logs 282334b0ed38
Using HTTP port: 8443
Creating API server client for https://10.43.0.1:443
Error while initializing connection to Kubernetes apiserver. This most likely means that the cluster is misconfigured (e.g., it has invalid apiserver certificates or service accounts configuration) or the --apiserver-host param points to a server that does not exist. Reason: the server has asked for the client to provide credentials
Refer to the troubleshooting guide for more information: https://github.com/kubernetes/dashboard/blob/master/docs/user-guide/troubleshooting.mdAfter i got the above error, i again searched online and tried few things. Finally, this link helped. After i executed the following commands on all agent nodes, Kubernetes dashboard finally started working!
docker volume rm etcd
rm -rf /var/etcd/backups/*None of your pods running, you need to resolve that issue first. try to restart the whole cluster and see all above pods in running status.