We have 3-4 different NetworkPolicy in our Namespace and they are applied based on Pod Selector. Want to know is there any way from Pod side to know which NetworkPolicy is applied on it?
If POD selector used you can use the simple way
kubectl get pod -l \
$( \
kubectl get netpolicies <netpolicy-name> \
-o jsonpath="{.spec.podSelector.matchLabels}"| \
jq -r 'to_entries|map("\(.key)=\(.value)")[]' \
)
This will get the policy selector and use it as input and list the pods
Any way from Pod side
There is no POD side you can check, however I read somewhere kubectl describe pod-name could show Network Policies I tested not showing at least in minikube
So you can use the above command or describe the networkpolicy itself to get POD selector and get an idea.
kubectl describe networkpolicies <name of policy>
The output of kubectl get network policy should display the pod-selector.
After that you can use kubectl get pod -l key=value to list the pods affected.
you can automate this using a bash script/function.
I would also recommend checking "kubectl np-viewer" which is a kubectl plugin, can be found here. This plugin has what you are asking for out of box.
kubectl np-viewer -p pod-name prints network policies rules affecting a specific pod in the current namespace
I ran:
kubectl api-resources | grep "External"
externalmetrics metrics.aws true ExternalMetric
I want to delete this metrics.aws API resource, but I am not even sure how it was deployed. How can I delete this safely?
If it is a not a standard resource, then It might be implemented as a "Customer Resource Definition (crds)"
kubectl get crds | grep externalmetrics
Check if there are any Custom Resources created under this crd and delete them if there any :
kubectl get externalmetrics
kubectl delete externalmetrics --all
Then delete that CRD
kubectl delete crd externalmetrics
Check if it is gone from api-resources list
kubectl get api-resources
Update:
If you see error: the server doesn't have a resource type "v1beta1" error then run the following command to remove it:
kubectl delete apiservice v1beta1.metrics.k8s.io
I use config connector https://cloud.google.com/config-connector/docs/overview
I create gcp resources with CRDs that config connector provides:
kind: IAMServiceAccount
kind: StorageBucket
etc
Now what I'd really like is to be able to get a simple list of each resource and its status (if it was created successfully or not). Where each resource is a single line that's something like: kind, name, status, etc
Is there a way with kubectl to get a list of all resources that were created by an operator like this? I suppose I could manually label all these resources and try to select with a label but I really don't want to do that
Edit
Per the comment I could do this, but curious if there is a less unwieldy command
kubectl get crds --selector cnrm.cloud.google.com/managed-by-kcc=true \
-o=jsonpath='{range .items[*]}{.metadata.name}{"\n"}{end}' | xargs -n 1 \
kubectl get -Ao jsonpath='{range .items[*]}{" Kind: "}{#.kind}{"Name: "}{#.metadata.name}{" Status: "}{#.status.conditions[].status}{" Reason: "}{#.status.conditions[].reason}{"\n"}{end}' --ignore-not-found
I've made a bit of research on this topic and I found 2 possible solutions to retrieve all the resources that were created by config-connector:
$ kubectl api-resources way
$ kubectl get-all/ketall way with labels (please see the explanation as it's not installed by default)
The discussion that is referencing similar issue can be found here:
Github.com: Kubernetes: kubectl: Issue 151
$ kubectl api-resources
As pointed in the comment I made you can use the following expression:
kubectl get crds --selector cnrm.cloud.google.com/managed-by-kcc=true -o=jsonpath='{range .items[*]}{.metadata.name}{"\n"}{end}' | xargs -n 1 kubectl get --ignore-not-found
Dissecting this solution:
kubectl get crds --selector cnrm.cloud.google.com/managed-by-kcc=true
retrieve the Customer Resource Definitions that have a matching selector
-o=jsonpath='{range .items[*]}{.metadata.name}{"\n"}{end}'
use the jsonpath to retrieve only the value stored in .metadata.name key (get the name of the crd)
| xargs -n 1 kubectl get
pipe the output to the xargs and use each CRD retrieved from previous command to run $ kubectl get <RESOURCE>
--ignore-not-found
do not display a message about missing resource
This command could also be altered to suit the specific needs as it's shown in the question.
A side note!
Similar command is referenced in the github link I pasted above:
Github.com: Kubernetes: kubectl: Issues 151: Comment 402003022
$ kubectl get-all/ketall
Above commands can be used to retrieve all of the resources in the cluster. They are not available in default kubectl and they need additional configuration.
More reference about the installation can be found in this github page:
Github.com: Corneliusweig: Ketall
Using the approach described in the official Kubernetes documentation:
Labels are intended to be used to specify identifying attributes of objects
Kubernetes.io: Docs: Concepts: Overview: Working with objects: Labels
You can label those resources created by config connector (I know that you would like to avoid it) and look for this resources like:
$ kubectl get-all -l look=here
NAME NAMESPACE AGE
storagebucket.storage.cnrm.cloud.google.com/config-connector-bucket config-connector 135m
storagebucket.storage.cnrm.cloud.google.com/config-connector-bucket-test config-connector 13s
This resources have the .metadata.labels.look=here added to it's definitions.
Additional resources:
Cloud.google.com: Config Connector: Docs: How to: Getting Started
Thenewstack.io: Tutorial use google config connector to manage a gcp cloud sql database
There is also a way suggested in GCP config-connector docs:
kubectl get gcp
from https://cloud.google.com/config-connector/docs/how-to/monitoring-your-resources#listing_all_resources
I am running the command
kubectl create -f mypod.yaml --namespace=mynamespace
as I need to specify the environment variables through a configMap I created and specified in the mypod.yaml file. Kubernetes returns
pod/mypod created
but kubectl get pods doesn't show it in my list of pods and I can't access it by name as if it does not exist. However, if I try to create it again, it says that the pod is already created.
What may cause this, and how would I diagnose the problem?
By default, kubectl commands operate in the default namespace. But you created your pod in the mynamespace namespace.
Try one of the following:
kubectl get pods -n mynamespace
kubectl get pods --all-namespaces
Include:
Daemon Sets
Deployments
Jobs
Pods
Replica Sets
Replication Controllers
Stateful Sets
Services
...
If has replicationcontroller, when delete some deployments they will regenerate. Is there a way to make kubenetes back to initialize status?
Method 1: To delete everything from the current namespace (which is normally the default namespace) using kubectl delete:
kubectl delete all --all
all refers to all resource types such as pods, deployments, services, etc. --all is used to delete every object of that resource type instead of specifying it using its name or label.
To delete everything from a certain namespace you use the -n flag:
kubectl delete all --all -n {namespace}
Method 2: You can also delete a namespace and re-create it. This will delete everything that belongs to it:
kubectl delete namespace {namespace}
kubectl create namespace {namespace}
Note (thanks #Marcus): all in kubernetes does not refers to every kubernetes object, such as admin level resources (limits, quota, policy, authorization rules). If you really want to make sure to delete eveything, it's better to delete the namespace and re-create it. Another way to do that is to use kubectl api-resources to get all resource types, as seen here:
kubectl delete "$(kubectl api-resources --namespaced=true --verbs=delete -o name | tr "\n" "," | sed -e 's/,$//')" --all
Kubernetes Namespace would be the perfect options for you. You can easily create namespace resource.
kubectl create -f custom-namespace.yaml
$ apiVersion: v1
kind: Namespace
metadata:
name:custom-namespace
Now you can deploy all of the other resources(Deployment,ReplicaSet,Services etc) in that custom namespaces.
If you want to delete all of these resources, you just need to delete custom namespace. by deleting custom namespace, all of the other resources would be deleted. Without it, ReplicaSet might create new pods when existing pods are deleted.
To work with Namespace, you need to add --namespace flag to k8s commands.
For example:
kubectl create -f deployment.yaml --namespace=custom-namespace
you can list all the pods in custom-namespace.
kubectl get pods --namespace=custom-namespace
You can also delete Kubernetes resources with the help of labels attached to it. For example, suppose below label is attached to all resource
metadata:
name: label-demo
labels:
env: dev
app: nginx
now just execute the below commands
deleting resources using app label
$ kubectl delete pods,rs,deploy,svc,cm,ing -l app=nginx
deleting resources using envirnoment label
$ kubectl delete pods,rs,deploy,svc,cm,ing -l env=dev
can also try kubectl delete all --all --all-namespaces
all refers to all resources
--all refers to all resources, including uninitialized ones
--all-namespaces in all all namespaces
First backup your namespace resources and then delete all resources found with the get all command:
kubectl get all --namespace={your-namespace} -o yaml > {your-namespace}.yaml
kubectl delete -f {your-namespace}.yaml
Nevertheless, still some resources exists in your cluster.
Check with
kubectl api-resources --verbs=list --namespaced -o name | xargs -n 1 kubectl get --show-kind --ignore-not-found --namespace {your-namespace}
If you really want to COMPLETELY delete your namespace, go ahead with:
kubectl delete namespace {your-namespace}
(tested with Client v1.23.1 and Server v1.22.3)
In case if you want to delete all K8S resources in the cluster. Then, easiest way would be to delete the entire namespace.
kubectl delete ns <name-space>
kubectl delete deploy,service,job,statefulset,pdb,networkpolicy,prometheusrule,cm,secret,ds -n namespace -l label
kubectl delete all --all
to delete all the resource in cluster.
after deleting all resources k8's will again relaunch the default services for cluster.