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Installing Grafana on Ubuntu 16.06

Following the install instructions here:

Add the repo to /etc/apt/sources.list and install with apt-get:

deb https://packagecloud.io/grafana/stable/debian/ jessie main

Add key:

curl https://packagecloud.io/gpg.key | sudo apt-key add -

Update and install:

sudo apt-get update
sudo apt-get install grafana

Start up the server service:

sudo service grafana-server start

To start at boot:

sudo update-rc.d grafana-server defaults

Up!

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Allowing user on CentOS to run docker command without sudo

Out of the box for a Docker install on CentOS 7, you have to sudo the docker command to interact with Docker. Per the post-install steps here, create a docker group and add your user to that group:

sudo groupadd docker

sudo usermod -aG docker youruser

Logging off and back on again, you should now be able to run the docker command without sudo.

On CentOS 7 this still didn’t work for me. Following this post, it appeared that docker.sock was owned by root and in the group root:

$ ls -l /var/run/docker.sock

srw-rw---- 1 root root 0 Oct 21 15:42 /var/run/docker.sock

Changing the group ownership:

$ sudo chown root:docker /var/run/docker.sock

$ ls -l /var/run/docker.sock

srw-rw---- 1 root docker 0 Oct 21 15:42 /var/run/docker.sock

After logging back on, now can run docker commands without sudo.

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Deploying kubernetes Dashboard to a kubeadm created cluster

Per installations steps here, to deploy the dashboard:

kubectl --kubeconfig ./admin.conf apply -f https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml

The start the local proxy:

./kubectl --kubeconfig ./admin.conf proxy

Accessing via http://localhost:8001/ui, gives this error:

{
  "kind": "Status",
  "apiVersion": "v1",
  "metadata": {
    
  },
  "status": "Failure",
  "message": "no endpoints available for service \"kubernetes-dashboard\"",
  "reason": "ServiceUnavailable",
  "code": 503
}

Checking what’s currently running with:

./kubectl --kubeconfig ./admin.conf get pods --all-namespaces

Looks like the dashboard app is not happy:

kube-system   kubernetes-dashboard-747c4f7cf-p8blw          0/1       CrashLoopBackOff   22         1h

Checking the logs for the dashboard:

./kubectl --kubeconfig ./admin.conf logs kubernetes-dashboard-747c4f7cf-p8blw --namespace=kube-system

2017/10/19 03:35:51 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: Get https://10.96.0.1:443/version: dial tcp 10.96.0.1:443: getsockopt: no route to host

OK.

I setup my master node using the flannel overlay. I don’t know if this makes any difference or not, but I noticed this article using kubeadm used Weave Net instead. Not knowing how to move forward (and after browsing many posts and tickets on issues with kubeadm with Dashboard), knowing at least that kubadm + Weave Net works for installing dashboard, so I tried this approach instead.

After re-initializing and the adding weave-net, my pods are all started:

$ kubectl get pods –all-namespaces

NAMESPACE     NAME                                          READY     STATUS    RESTARTS   AGE

kube-system   etcd-unknown000c2960f639                      1/1       Running   0          11m

kube-system   kube-apiserver-unknown000c2960f639            1/1       Running   0          11m

kube-system   kube-controller-manager-unknown000c2960f639   1/1       Running   0          11m

kube-system   kube-dns-545bc4bfd4-nhrw7                     3/3       Running   0          12m

kube-system   kube-proxy-cgn45                              1/1       Running   0          4m

kube-system   kube-proxy-dh6jm                              1/1       Running   0          12m

kube-system   kube-proxy-spxm5                              1/1       Running   0          5m

kube-system   kube-scheduler-unknown000c2960f639            1/1       Running   0          11m

kube-system   weave-net-gs8nh                               2/2       Running   0          5m

kube-system   weave-net-jkkql                               2/2       Running   0          4m

kube-system   weave-net-xb4hx                               2/2       Running   0          10m

 

Trying to add the dashboard once more:

kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/recommended/kubernetes-dashboard.yaml

… and, o. m. g. :

$ kubectl get pods –all-namespaces

NAMESPACE     NAME                                          READY     STATUS    RESTARTS   AGE

kube-system   etcd-unknown000c2960f639                      1/1       Running   0          37m

kube-system   kube-apiserver-unknown000c2960f639            1/1       Running   0          37m

kube-system   kube-controller-manager-unknown000c2960f639   1/1       Running   0          37m

kube-system   kube-dns-545bc4bfd4-nhrw7                     3/3       Running   0          38m

kube-system   kube-proxy-cgn45                              1/1       Running   0          30m

kube-system   kube-proxy-dh6jm                              1/1       Running   0          38m

kube-system   kube-proxy-spxm5                              1/1       Running   0          31m

kube-system   kube-scheduler-unknown000c2960f639            1/1       Running   0          37m

kube-system   kubernetes-dashboard-747c4f7cf-jgmgt          1/1       Running   0          4m

kube-system   weave-net-gs8nh                               2/2       Running   0          31m

kube-system   weave-net-jkkql                               2/2       Running   0          30m

kube-system   weave-net-xb4hx                               2/2       Running   0          36m

Starting kubectl proxy and hitting localhost:8001/ui now gives me:

Error: 'malformed HTTP response "\x15\x03\x01\x00\x02\x02"'
Trying to reach: 'http://10.32.0.3:8443/'

Reading here, trying the master node directly:

https://192.168.1.80:6443/api/v1/namespaces/kube-system/services/https:kubernetes-dashboard:/proxy/

gives a different error:

{
  "kind": "Status",
  "apiVersion": "v1",
  "metadata": {
    
  },
  "status": "Failure",
  "message": "services \"https:kubernetes-dashboard:\" is forbidden: User \"system:anonymous\" cannot get services/proxy in the namespace \"kube-system\"",
  "reason": "Forbidden",
  "details": {
    "name": "https:kubernetes-dashboard:",
    "kind": "services"
  },
  "code": 403
}

… but reading further ahead, it seems accessing via the /ui url is not correctly working, you need to access via the url in the docs here,  which says the correct url is:

http://localhost:8001/api/v1/namespaces/kube-system/services/https:kubernetes-dashboard:/proxy/

and now I get an authentication page:

Time to read ahead on the authentication approaches.

List available tokens with:

kubectl -n kube-system get secret

Using the same token as per the docs (although at this point I’ve honestly no idea what the difference in permissions is for each of the different tokens):

./kubectl --kubeconfig admin.conf -n kube-system describe secret replicaset-controller-token-7tzd5

And then pasting the token value into the authentication dialog gets me logged on! There’s some errors about this token not having access to some features, but at this point I’ve just glad I’ve managed to get this deployed and working!

If you’re intested in the specific versions I’m using, this is deployed to CentOS 7, and kubernetes version:

$ kubectl version

Client Version: version.Info{Major:”1″, Minor:”8″, GitVersion:”v1.8.1″, GitCommit:”f38e43b221d08850172a9a4ea785a86a3ffa3b3a”, GitTreeState:”clean”, BuildDate:”2017-10-11T23:27:35Z”, GoVersion:”go1.8.3″, Compiler:”gc”, Platform:”linux/amd64″}

Server Version: version.Info{Major:”1″, Minor:”8″, GitVersion:”v1.8.1″, GitCommit:”f38e43b221d08850172a9a4ea785a86a3ffa3b3a”, GitTreeState:”clean”, BuildDate:”2017-10-11T23:16:41Z”, GoVersion:”go1.8.3″, Compiler:”gc”, Platform:”linux/amd64″}

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