I was setting up a nginx cluster on google cloud, and I entered a wrong image name; instead of entering:
kubectl create deploy nginx --image=nginx:1.17.10
I entered:
kubectl create deploy nginx --image=1.17.10
and eventually after running kubectl get pods, It showed ImagePullBackOff as the status for the pod.
When I tried running the correct create deploy command above, It said "nginx" already exists.
When I tried doing kubernetes delete --all pods, the pod was recreated with a new ID but still had the same status, and still couldn't allow me to run the right 'kubectl create deploy' command above. Now I'm stuck.
How can I undo it?
You need to delete the deployment:
kubectl delete deploy nginx
Otherwise Kubernetes will recreate the pod on every shutdown.
You can see all your deployments with
kubectl get deploy
Edit the deployment via kubectl edit deployment DEPLOYMENT_NAME and change the image name.
Or
Edit the manifest file and append the file with a correct image mane and do a kubectl apply -f YAML file
First of all, your k8s cluster is trying to pull image 1.17.10 from public docker registry. But as there are no image exists with this name that's why it's get error. And when you have tried to delete your pods it will again try to create with same image name as your deployment is exists. For this reason you need to delete deployment rather then pods. Otherwise, deployment will automatically try to create deleted pod again.
you can actually check what was the error in your deployment with this command:
kubectl describe deploy nginx
For you the command will bekubectl delete deploy -n <Namespace_name> <deployment_name>. As you have created your deployment in default namespace you don't need to mention the namespace automatically it will be the default namespace.
you can delete deployment with this command:
kubectl delete deploy nginx
Related
I'm running the example in chapter "Service Discovery" of the book "Kubernetes up and running". The original command to run a deployment is kubectl run alpaca-prod --image=gcr.io/kuar-demo/kuard-amd64:blue --replicas=3 --port=8080 --labels="ver=1,app=alpaca,env=prod", however in K8s version 1.25, the --replicate parameter in run command is not supported any more. I planned to run without replica and then use "kubectl scale" to scale the deployment later. Problem is the run command only creates a pod, not a deployment (the scale command expects a deployment). So how do i promote my pod to a deployment, my kubernetes verion is 1.25?
There is no way to promote it however you can change label and all those stuff but instead of that you can create the new deployment delete the existing POD.
So easy step you can take input of existing running POD to YAML file first
kubectl get pod <POD name> -o yaml > pod-spec.yaml
Create deployment spec YAML file now
kubectl create deployment deploymentname --image=imagename --dry-run=client -o yaml > deployment-spec.yaml
Edit the deployment-spec.yaml file
and in other tab pod-spec.yaml you can copy the Spec part from POD file to new deployment file.
Once deployment-spec.yaml is ready you can apply it. Make sure if you are running service labels get matched properly
kubectl apply -f deployment-spec.yaml
Delete the single running POD
kubectl delete pod <POD name>
In kubernetes I have a command as
kubectl create deployment nginx --image=ewoutp/docker-nginx-curl -n web
What should I run if I want to create this inside openshift cluster
I tried this
oc create deployment nginx --image=ewoutp/docker-nginx-curl -n web
I am getting error as error:
no matches for extensions/, Kind=Deployment
Can someone help me?
It might indicate that your openshift cluster is not running. Check oc status to view status of your current project. If it is not running you should create new project.
If you cluster is running you can run oc create deployment nginx --image=ewoutp/docker-nginx-curl -n web -o yaml to verify if apiVersion is correct. Currently used version is apps/v1. If it is incorrect you can save it to file and edit to match current version.
I have followed instructions from this blog post to set up a k3s cluster on a couple of raspberry pi 4:
I'm now trying to get my hands dirty with traefik as front, but I'm having issues with the way it has been deployed as a 'HelmChart' I think.
From the k3s docs
It is also possible to deploy Helm charts. k3s supports a CRD
controller for installing charts. A YAML file specification can look
as following (example taken from
/var/lib/rancher/k3s/server/manifests/traefik.yaml):
So I have been starting up my k3s with the --no-deploy traefik option to manually add it with settings. So I therefore manually apply a yaml like this:
apiVersion: helm.cattle.io/v1
kind: HelmChart
metadata:
name: traefik
namespace: kube-system
spec:
chart: https://%{KUBERNETES_API}%/static/charts/traefik-1.64.0.tgz
set:
rbac.enabled: "true"
ssl.enabled: "true"
kubernetes.ingressEndpoint.useDefaultPublishedService: "true"
dashboard:
enabled: true
domain: "traefik.k3s1.local"
But when trying to iterate over settings to get it working as I want, I'm having trouble tearing it down. If I try kubectl delete -f on this yaml it just hangs indefinitely. And I can't seem to find a clean way to delete all the resources manually either.
I've been resorting now to just reinstall my entire cluster over and over because I can't seem to cleanup properly.
Is there a way to delete all the resources created by a chart like this without the helm cli (which I don't even have)?
Are you sure that kubectl delete -f is hanging?
I had the same issue as you and it seemed like kubectl delete -f was hanging, but it was really just taking a long time.
As far as I can tell, when you issue the kubectl delete -f a pod in the kube-system namespace with a name of helm-delete-* should spin up and try to delete the resources deployed via helm. You can get the full name of that container by running kubectl -n kube-system get pods, find the one with kube-delete-<name of yaml>-<id>. Then use the pod name to look at the logs using kubectl -n kube-system logs kube-delete-<name of yaml>-<id>.
An example of what I did was:
kubectl delete -f jenkins.yaml # seems to hang
kubectl -n kube-system get pods # look at pods in kube-system namespace
kubectl -n kube-system logs helm-delete-jenkins-wkjct # look at the delete logs
I see two options here:
Use the --now flag to delete your yaml file with minimal delay.
Use --grace-period=0 --force flags to force delete the resource.
There are other options but you'll need Helm CLI for them.
Please let me know if that helped.
I am new to Kubernetes so pardon me if you find my question noob.
I have created a Daemonset called testDaemon.yml which is having a service in it called testService. Both were created but now I have made some minor changes and I need to re-create it.
I tried deleting the services and daemonset:
kubectl delete ds testDaemon
kubectl delete svc testService
but both of them is getting recreated everytime I delete them and I am getting an error that services "testService" already existswhen I run kubectl create -f testDaemon.yml again.
What should I do to remove the DaemonSet completely or update the same with the new template?
You can delete it using
kubectl delete -f testDaemon.yml
It will delete the statefulset and service both.
I am starting exploring runnign docker containers with Kubernetes. I did the following
Docker run etcd
docker run master
docker run service proxy
kubectl run web --image=nginx
To cleanup the state, I first stopped all the containers and cleared the downloaded images. However I still see pods running.
$ kubectl get pods
NAME READY STATUS RESTARTS AGE
web-3476088249-w66jr 1/1 Running 0 16m
How can I remove this?
To delete the pod:
kubectl delete pods web-3476088249-w66jr
If this pod is started via some replicaSet or deployment or anything that is creating replicas then find that and delete that first.
kubectl get all
This will list all the resources that have been created in your k8s cluster. To get information with respect to resources created in your namespace kubectl get all --namespace=<your_namespace>
To get info about the resource that is controlling this pod, you can do
kubectl describe web-3476088249-w66jr
There will be a field "Controlled By", or some owner field using which you can identify which resource created it.
When you do kubectl run ..., that's a deployment you create, not a pod directly. You can check this with kubectl get deploy. If you want to delete the pod, you need to delete the deployment with kubectl delete deploy DEPLOYMENT.
I would recommend you to create a namespace for testing when doing this kind of things. You just do kubectl create ns test, then you do all your tests in this namespace (by adding -n test). Once you have finished, you just do kubectl delete ns test, and you are done.
If you defined your object as Pod then
kubectl delete pod <--all | pod name>
will remove all of the generated Pod. But, If wrapped your Pod to Deployment object then running the command above only will trigger a re-creation of them.
In that case, you need to run
kubectl delete deployment <--all | deployment name>
That will also remove the Service object that is related to the deleted Deployment