I'm new to OpenShift and Kubernetes.
I need to access kube-apiserver on existing OpenShift environment
oc v3.10.0+0c4577e-1
kubernetes v1.10.0+b81c8f8
how do I know kube-apiserver is already installed, or how to get it installed?
I checked all the containers and there is no even such path /etc/kubernetes/manifests.
Here is the list of docker processes on all clusters, could it hide behind one of these?
k8s_fluentd-elasticseark8s_POD_logging
k8s_POD_tiller-deploy
k8s_api_master-api-ip-...ec2.internal_kube-system
k8s_etcd_master-etcd-...ec2.internal_kube-system
k8s_POD_master-controllers
k8s_POD_master-api-ip-
k8s_POD_kube-state
k8s_kube-rbac-proxy
k8s_POD_node-exporter
k8s_alertmanager-proxy
k8s_config-reloader
k8s_POD_alertmanager_openshift-monitoring
k8s_POD_prometheus
k8s_POD_cluster-monitoring
k8s_POD_heapster
k8s_POD_prometheus
k8s_POD_webconsole
k8s_openvswitch
k8s_POD_openshift-sdn
k8s_POD_sync
k8s_POD_master-etcd
If you just need to verify that the cluster is up and running then you can simply run oc get nodes which communicates with the kube-apiserver to retrieve information.
oc config view will show where kube-apiserver is hosted under the clusters -> cluster -> server section. On that host machine you can run command docker ps to display the running containers, which should include the kube-apiserver
Related
We setup a rancher cluster with 3 nodes for testing and I would like to apply for k8s conformance using this rancher cluster. However, while running sonobuoy it returns error
ERRO[0000] could not create sonobuoy client: failed to get rest config: invalid configuration: no configuration has been provided
It seems like Rancher does not have any kubernates binaries built-in (Kubectl, kubeadm etc). May I know if it is possible to be k8s conformance on a rancher cluster?
You should have kubeernetes cluster kubeconfig localy where you are running sonobuoy.
from Rancher documentation: How to Manage Kubernetes With Kubectl:
RKE:
When you create a Kubernetes cluster with RKE, RKE creates a
kube_config_rancher-cluster.yml file in the local directory that
contains credentials to connect to your new cluster with tools like
kubectl.
You can copy this file to $HOME/.kube/config or, if you are working
with multiple Kubernetes clusters
Rancher-Managed Kubernetes Clusters:
Within Rancher, you can download a kubeconfig file through the web UI
and use it to connect to your Kubernetes environment with kubectl.
From the Rancher UI, click on the cluster you would like to connect to
via kubectl. On the top right-hand side of the page, click the
Kubeconfig File button: Click on the button for a detailed look at
your config file as well as directions to place in ~/.kube/config.
Upon copying your configuration to ~/.kube/config, you will be able to
run kubectl commands without having to specify the –-kube-config file
location:
Check First launch with sonobuoy requests for a configuration - maybe it will be useful for you.
Also, look here - just for you: Conformance tests for Rancher 2.x Kubernetes
Run Conformance Test
Once you Rancher Kubernetes cluster is active, Fetch it's kubeconfig.yml file and save it locally.
Download a sonobuoy binary release of the CLI, or build it yourself by running:
$ go get -u -v github.com/heptio/sonobuoy
Configure your kubeconfig file by running:
$ export KUBECONFIG="/path/to/your/cluster/kubeconfig.yml"
Run sonobuoy:
$ sonobuoy run
Watch the logs:
$ sonobuoy logs
Check the status:
$ sonobuoy status
Once the status commands shows the run as completed, you can download the results tar.gz file:
$ sonobuoy retrieve
Newbie setup :
Created First project in GCP
Created cluster with default, 3 nodes. Node version 1.7.6. cluster master version 1.7.6-gke.1.
Deployed aan application in a pod, per example.
Able to access "hello world" and the hostname, using the external-ip and the port.
In GCP / GKE webpage of my cloud console, clicked "discovery and loadbalancing", I was able to see the "kubernetes-dashboard" process in green-tick, but cannot access throught the IP listed. tried 8001,9090, /ui and nothing worked.
not using any cloud shell or gcloud commands on my local laptop. Everything is done on console.
Questions :
How can anyone access the kubernetes-dashboard of the cluster created in console?
docs are unclear, are the dashboard components incorporated in the console itself? Are the docs out of sync with GCP-GKE screens?
tutorial says run "kubectl proxy" and then to open
"http://localhost:8001/ui", but it doesnt work, why?
If you create a cluster with with version 1.9.x or greater, then u can access using tokens.
get secret.
kubectl -n kube-system describe secrets `kubectl -n kube-system get secrets | awk '/clusterrole-aggregation-controller/ {print $1}'` | awk '/token:/ {print $2}'
Copy secret.
kubectl proxy.
Open UI using 127.0.0.1:8001/ui. This will redirect to login page.
there will be two options to login, kubeconfig and token.
Select token and paste the secret copied earlier.
hope this helps
It seems to be an issue with the internal Kubernetes DNS service starting at version 1.7.6 on Google Cloud.
The solution is to access the dashboard at this endpoint instead:
http://localhost:8001/api/v1/proxy/namespaces/kube-system/services/kubernetes-dashboard
Github Issue links:
https://github.com/kubernetes/dashboard/issues/2368
https://github.com/kubernetes/kubernetes/issues/52729
The address of the dashboard service is only accessible from inside of the cluster. If you ssh into a node in your cluster, you should be able to connect to the dashboard. You can verify this by noticing that the address is within the services CIDR range for your cluster.
The dashboard in running as a pod inside of your cluster with an associated service. If you open the Workloads view you will see the kubernetes-dashboard deployment and can see the pod that was created by the deployment. I'm not sure which docs you are referring to, since you didn't provide a link.
When you run kubectl proxy it creates a secure connection from your local machine into your cluster. It works by connecting to your master and then running through a proxy on the master to the pod/service/host that you are connecting to via an ssh tunnel. It's possible that it isn't working because the ssh tunnels are not running; you should verify that your project has newly created ssh rules allowing access from the cluster endpoint IP address. Otherwise, if you could explain more about how it fails, that would be useful for debugging.
First :
gcloud container clusters get-credentials cluster-1 --zone my-zone --project my-project
Then find your kubernetes dashboard endpoint doing :
kubectl cluster-info
It will be something like https://42.42.42.42/api/v1/namespaces/kube-system/services/kubernetes-dashboard/proxy
Install kube-dashboard
kubectl apply -f https://raw.githubusercontent.com/kubernetes/dashboard/v1.10.1/src/deploy/recommended/kubernetes-dashboard.yaml
Run:
$ kubectl proxy
Access:
http://localhost:8001/api/v1/namespaces/kube-system/services/https:kubernetes-dashboard:/proxy/#!/login
Docker: 1.12.6
rancher/server: 1.5.10
rancher/agent: 1.2.2
Tried two ways to install Kubernetes cluster on rancher/server.
Method 1: Use Kubernetes environment
Infrastructure/Hosts
Agent hosts disconnected sometimes.
Stacks
All green except kubernetes-ingress-lbs. It has 0 containers.
Method 2: Use Default environment
Infrastructure/Hosts
Set some labels to rancher server and agent hosts.
Stacks
All green except kubernetes-ingress-lbs. It has 0 containers.
Both of them have this issue: kubernetes-ingress-lbs 0 services 0 containers. Then can't access Kubernetes dashboard.
Why didn't been installed by rancher?
And, is it necessary to add those labels for Kubernetes cluster?
Here is RIGHT Kubernetes Cluster deployed on Rancher server:
Turning on the Show System, you can find the service of kubernetes-dashboard under the namespace of kube-system.
Well, by using the version of kubernetes is v1.5.4, you should prepare in advance to pull the below Docker Images:
By reading rancher/catalog and rancher/kuberetes-package, you can know and even modify the config files(like docker-compose.yml, rancher-compose.yml and so on) by yourself.
When you enable to "Show System" containers in the UI, you should be able to see the dashboard container running under Namespace: kube-system. If this container is not running then the dashboard will not be able to load.
You might have to enable kubernetes add-on service within rancher environment template.
manage environments >> edit kubernetes default template >> enable add-on service and save the new template with the preferred name.
Now launch the cluster using customized templates.
I've installed Kubernetes via Vagrant on OS X and everything seems to be working fine, but I'm unsure how kubectl is able to communicate with the master node despite being local to the workstation filesystem.
How is this implemented?
kubectl has a configuration file that specifies the location of the Kubernetes apiserver and the client credentials to authenticate to the master. All of the commands issued by kubectl are over the HTTPS connection to the apiserver.
When you run the scripts to bring up a cluster, they typically generate this local configuration file with the parameters necessary to access the cluster you just created. By default, the file is located at ~/.kube/config.
In addition to what Robert said: the connection between your local CLI and the cluster is controlled through kubectl config set, see the docs.
The Getting started with Vagrant section of the docs should contain everything you need.
I'm setting up a kubernetes cluster on digitalocean ubuntu machines. I got the cluster up and running following this get started guide ubuntu. During the setup the ENABLE_NODE_LOGGING, ENABLE_CLUSTER_LOGGING and ENABLE_CLUSTER_DNS variables are set to true in the config-default.sh.
However there is no controller, services created for elasticsearch/kabana. I did have to run the deployAddon.sh manually for the skydns, do I need to do the same for logging and monitoring ? or am I missing something in the default configuration.
By default the logging and monitoring services are not in the default namespace.
You should be able to see if the services are running with kubectl cluster-info.
To look at the individual services/controllers, specify the kube-system namespace:
kubectl get service --namespace=kube-system
By default, logging and monitor is not enabled if you are installing kubernetes on ubuntu machines. It looks like someone has copied the config-default.sh script from some other folder, hence the variables ENABLE_NODE_LOGGING and ENABLE_CLUSTER_LOGGING are copied but are not used to bring up the relevant logging deployments and services.
As #Jon Mumm said, kubectl cluster-info gives you the info. But if you want to install the logging service, go to
kubernetes/cluster/addons/fluentd-elasticsearch
and run
kubectl create -f es-controller.yaml -f es-service.yaml -f kibana-controller.yaml -f kibana-service.yaml
with right setup. Change the yaml files to suit your configuration and ensure kubectl is in your path.
Update 1: This will bring up kibana and logstash services