enter image description hereI tried to used the instructions from this link https://github.com/kubernetes/heapster/blob/master/docs/influxdb.md but I was not able to install it. specifically I dont know what this instruction means "Ensure that kubecfg.sh is exported." I dont even know where I can find this I did this sudo find / -name "kubecfg.sh" and I found no results.
moving on to the next step "kubectl create -f deploy/kube-config/influxdb/" when I did this it says kube-system not found I am using latest version of kubernetes version 1.0.1
These instructions are broken can any one provide some instructions on how to install this? I have kubernetes cluster up and running I was able to create and delete pods and so on and default is the only namespace I have when i do kubectl get pods,svc,rc --all-namespaces
Changing kube-system to default in the yaml files is just getting me one step further but I am unable to access the UI and so on. so installing kube-system makes more sense however I dont know how to do it and any instructions on installing influxdb and grafana to get it up and running will be very helpful
I am using latest version of kubernetes version 1.0.1
FYI, the latest version is v1.2.3.
... it says kube-system not found
You can create the kube-system namespace by running
kubectl create namespace kube-system.
Hopefully once you've created the kube-system namespace the rest of the instructions will work.
We had the same issue deploying grafana/influxdb. So we dug into it:
Per https://github.com/kubernetes/heapster/blob/master/docs/influxdb.md since we don’t have an external load balancer, we changed the port type on the grafana service to NodePort which made it accessible at port 30397.
Then looked at the controller configuration here: https://github.com/kubernetes/heapster/blob/master/deploy/kube-config/influxdb/influxdb-grafana-controller.yaml and noticed the comment about using the api-server proxy which we wouldn’t be doing by exposing the NodePort, so we deleted the GF_SERVER_ROOT_URL environment variable from the config. At that point Grafana at least seemed to be running, but it looked like it was having trouble reaching influxdb.
We then changed the datasource to use localhost instead of monitoring-influxd and was able to connect. We're getting data on the cluster usage now, though individual pod data doesn’t seem to be working.
Related
As the question shows, I have very low knowledge about kubernetes. Following a tutorial, I made a Kubernetes cluster to run a web app on a local server using Minikube. I have applied the kubernetes components and they are running but the Web-Server does not respond to HTTP requests. My problem is that all the system that I have created is like a black box for me and I have literally no idea how to open it and see where the problem is. Can you explain how I can debug such implementaions in a wise way. Thanks.
use a tool like https://github.com/kubernetes/kubernetes-dashboard
You can install kubectl and kubernetes-dashboard in a k8s cluster (https://kubernetes.io/docs/tasks/tools/install-kubectl/), and then use the kubectl command to query information about a pod or container, or use the kubernetes-dashboard web UI to query information about the cluster.
For more information, please refer to https://kubernetes.io/
kubectl get pods
will show you all your pods and their status. A quick check to make sure that all is at least running.
If there are pods that are unhealthy, then
kubectl describe pod <pod name>
will give some more information.. eg image not found etc
kubectl log <pod name> --all
is often the next step , use -f to follow the logs as you exercise your api.
It is possible to link up images running in a pod with most ide debuggers, but instructions will differ depending on language and ide used...
I setup a private K8S cluster with RKE 1.2.2 and so my K8S version is 1.19. We have some internal services, and it is necessary to access each other using custom FQDN instead of simple service names. As I searched the web, the only solution I found is adding rewrite records for CoreDNS ConfigMap described in this REF. However, this solution results in manual configuration, and I want to define a record automatically during service setup. Is there any solution for this automation? Does CoreDNS have such an API to add or delete rewrite records?
Note1: I also tried to mount the CoreDNS's ConfigMap and update it via another pod, but the content is mounted read-only.
Note2: Someone proposed calling kubectl get cm -n kube-system coredns -o yaml | sed ... | kubectl apply .... However, I want to automate it during service setup or in a pod or in an initcontainer.
Note3: I wish there were something like hostAliases for services, something called serviceAliases for internal services (ClusterIP).
Currently, there is no ready solution for this.
Only thing comes to my mind is to use MutatingAdmissionWebhook. It would need catch moment, when new Kubernetes service was created and then modify ConfigMap for CoreDNS as it's described in CoreDNS documentation.
After that, you would need to reload CoreDNS configuration to apply new configuration from ConfigMap. To achieve that, you can use reload plugin for CoreDNS. More details about this plugin can be found here.
Instead of above you can consider using sidecarContainer for CoreDNS, which will send SIGUSR1 signal to CoreDNS conatiner.
Example of this method can be found in this Github thread.
We are developing k8s CSI driver
Currently in order to upgrade driver we delete the installed operator pods, cdrs and roles and recreate them from new version images.
What is suggested way to do upgrade? Or is uninstall/install is the suggested method?
I couldn't find any relevant information
We also have support of installing from OpenShift. Is there any difference regarding upgrade from OpenShift?
You should start from this documentation:
This page describes to CSI driver developers how to deploy their
driver onto a Kubernetes cluster.
Especially:
Deploying a CSI driver onto Kubernetes is highlighted in detail in
Recommended Mechanism for Deploying CSI Drivers on Kubernetes.
Also, you will find there all the necessary info with an example.
Your question lacks some details regarding your use case but I strongly recommend starting from the guide I have presented you.
Please, let me know if that helps.
CSI drivers can differ, but I believe the best approach is to do rolling update of your plugin's DaemonSet. It will happen automatically once you apply the new DaemonSet configuration, e.g. newer docker image.
For more details, see https://kubernetes.io/docs/tasks/manage-daemon/update-daemon-set/
For example:
kubectl get -n YOUR-NAMESPACE daemonset YOUR-DAEMONSET --export -o yaml > plugin.yaml
vi plugin.yaml # Update your image tag(s)
kubectl apply -n YOUR-NAMESPACE -f plugin.yaml
A shorted way to update just the image:
kubectl set image ds/YOUR-DAEMONSET-NAME YOUR-CONTAINER-NAME=YOUR-IMAGE-URL:YOUR-TAG -n YOUR-NAMESPACE
Note: I found that I also needed to restart (kill) the pod with the external provisioner. There's probably a more elegant way to handle this, but it works in a pinch.
kubectl delete pod -n YOUR-NAMESPACE YOUR-EXTERNAL-PROVISIONER-POD
I'm using Kubernetes 1.11 on Digital Ocean, when I try to use kubectl top node I get this error:
Error from server (NotFound): the server could not find the requested resource (get services http:heapster:)
but as stated in the doc, heapster is deprecated and no longer required from kubernetes 1.10
If you are running a newer version of Kubernetes and still receiving this error, there is probably a problem with your installation.
Please note that to install metrics server on kubernetes, you should first clone it by typing:
git clone https://github.com/kodekloudhub/kubernetes-metrics-server.git
then you should install it, WITHOUT GOING INTO THE CREATED FOLDER AND WITHOUT MENTIONING AN SPECIFIC YAML FILE , only via:
kubectl create -f kubernetes-metrics-server/
In this way all services and components are installed correctly and you can run:
kubectl top nodes
or
kubectl top pods
and get the correct result.
For kubectl top node/pod to work you either need the heapster or the metrics server installed on your cluster.
Like the warning says: heapster is being deprecated so the recommended choice now is the metrics server.
So follow the directions here to install the metrics server
I have been working on this for quite some time now, but google container engine has some missing documentation on installing addons.
First I thought I create my addons as yml files and install them into the kube-system namespace.
But the addon-manager apparently removes everything from the kube-system namespace that in its opinion does not belong there.
How do I add any kubernetes addon to my google container engine cluster?
For example I would like to install:
cluster-monitoring (heapster, influxdb, grafana addon)
The add-on manager is removing everything from the kube-system namespace that has the label addonmanager.kubernetes.io/mode: Reconcile which doesn't exist in a "source of truth" location. Since your resources aren't in the source of truth, they get removed.
You can remove that label and the add-on manager should leave your deployments alone. But I'd recommend running them in a different namespace instead.