Improve default kubectl behavior when it doesn't know what cluster to talk to

bgrant0607 commented 8 years ago

At minimum, we need to improve the error message: The connection to the server localhost:8080 was refused - did you specify the right host or port?

We might also want to consider not using localhost as the default, though we want to keep it aligned with our single-node dev cluster plans. kubernetes/kubernetes#24106

cc @kubernetes/kubectl @dlorenc @vishh

luxas commented 8 years ago

I think it should default to localhost, but I agree the message could be way more user-friendly

smarterclayton commented 8 years ago

An example of what we do in OpenShift: https://github.com/openshift/origin/blob/master/pkg/cmd/util/clientcmd/factory.go#L112

It belongs in the factory (since not all client tools will want / need that error) rather than in a more generic spot like cmdutil.CheckErr

bgrant0607 commented 8 years ago

Ref kubernetes/kubernetes#23726

pwittrock commented 8 years ago

I like the OpenShift error messaging more than what we have now. Does it make sense to point the user towards solutions for populating the config for turnkey solutions? Perhaps as an entry under kubectl config --help?

smarterclayton commented 8 years ago

kubectl config would be a good place (until Brian gets someone to move it) - I expect users to look there first.

nikhita commented 7 years ago

Hi, I'm new here and would like to work on this!

Would the following be a good way to tackle this issue?

Suggest the user to run kubectl config --help when the error occurs.
Add a few examples for kubectl config --help. Something like: https://github.com/kubernetes/kubernetes/blob/master/hack/local-up-cluster.sh#L743. However, examples are already present for subcommands (eg. kubectl config set-cluster --help). So would it make sense to do this?

bgrant0607 commented 7 years ago

@nikinath Thanks. Please email kubernetes-sig-cli@googlegroups.com.

bgrant0607 commented 7 years ago

cc @kubernetes/sig-cli-feature-requests

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bgrant0607 commented 6 years ago

/remove-lifecycle rotten

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ryanmcginnis commented 6 years ago

/remove-lifecycle stale

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nikhita commented 6 years ago

/remove-lifecycle stale

ssuchter commented 4 years ago

This issue is now hitting downstream projects (e.g. Istio). See this Istio discuss thread. The user didn't have a ~/.kube/config and got this inscrutable message:

Failed to wait for resources ready: Get http://localhost:8080/api/v1/namespaces/istio-system: dial tcp [::1]:8080: connect: connection refused

Fortunately the user noticed the localhost:8080 in there and was able to proceed.

I have the perception that localhost connections are very likely to succeed the first time they are queried (as opposed to off-host connections).

I'd propose that when kubectl (or other tools, perhaps?) specifically detects that:

It's talking to localhost
because it was the default, due to a non-existent ~/.kube/config
it cannot connect

It should output an error or warning saying something like:

Unable to connect to Kubernetes at localhost:8080. It's likely that you are trying to reach a different cluster, please configure it in a ~/.kube/config file.

lavalamp commented 4 years ago

Maybe it should just always print a warning when there's no .kube/config file. Warning: You have no ~/.kube/config; assuming a local cluster in insecure mode (localhost:8080). Please make a ~/.kube/config file to ensure you're talking to the cluster you intend to talk to.

Personally I think it'd be better to refuse to connect without an explicit destination, but almost certainly that'd be "fixing" a load-bearing bug.

penkong commented 4 years ago

did anybody find solution? run in fedora, somebody provide a sample /.kube/config file. plz

sftim commented 1 year ago

This is a kubectl issue /transfer kubectl

sftim commented 1 year ago

Could we deprecate not having a kubeconfig but still retain the (deprecated) existing behavior?

If we do that, we could output this for a failed connection:

Warning: no Kubernetes client configuration found.

The kubectl tool was not able to find a configuration for connecting to your Kubernetes cluster.
Previous versions of Kubernetes supported trying to connect without a Kubernetes configuration.
The tool can still use defaults to connect, but this is deprecated since Kubernetes 1.42 due to
concerns about security.

Additionally, when kubectl tried to use default values to connect, the connection to localhost
on port 8080 timed out after 10 seconds.

To learn how to configure kubectl, visit https://k8s.io/whatever

or, if the connection worked OK, something like:

Warning: no Kubernetes client configuration found. Using defaults.
Warning: insecure connection to Kubernetes control plane (no TLS).
NAME                                READY     STATUS    RESTARTS   AGE       LABELS
nginx-deployment-75675f5897-7ci7o   1/1       Running   0          18s       app=nginx,pod-template-hash=3123191453
nginx-deployment-75675f5897-kzszj   1/1       Running   0          18s       app=nginx,pod-template-hash=3123191453
nginx-deployment-75675f5897-qqcnn   1/1       Running   0          18s       app=nginx,pod-template-hash=3123191453

(bold: stderr; normal weight: stdout)

bgrant0607 commented 1 year ago

I don't remember which parts of this issue were in the client library vs kubectl, but it sounds reasonable to me.

BTW, we need a bot to notify the current people involved in the relevant SIG or something. Almost certainly these old issues don't have the right/best people subscribed to them.

sftim commented 1 year ago

I don't know about a bot, but I already mentioned it in Slack.

eddiezane commented 1 year ago

It's probably a good time to pull the trigger on adding a better warning here.

/triage accepted /assign @ShivamTyagi12345

ShivamTyagi12345 commented 1 year ago

Could we deprecate not having a kubeconfig but still retain the (deprecated) existing behavior?

If we do that, we could output this for a failed connection:

Warning: no Kubernetes client configuration found.

The kubectl tool was not able to find a configuration for connecting to your Kubernetes cluster. Previous versions of Kubernetes supported trying to connect without a Kubernetes configuration. The tool can still use defaults to connect, but this is deprecated since Kubernetes 1.42 due to concerns about security.

Additionally, when kubectl tried to use default values to connect, the connection to localhost on port 8080 timed out after 10 seconds.

To learn how to configure kubectl, visit https://k8s.io/whatever

or, if the connection worked OK, something like:

Warning: no Kubernetes client configuration found. Using defaults. Warning: insecure connection to Kubernetes control plane (no TLS). NAME READY STATUS RESTARTS AGE LABELS nginx-deployment-75675f5897-7ci7o 1/1 Running 0 18s app=nginx,pod-template-hash=3123191453 nginx-deployment-75675f5897-kzszj 1/1 Running 0 18s app=nginx,pod-template-hash=3123191453 nginx-deployment-75675f5897-qqcnn 1/1 Running 0 18s app=nginx,pod-template-hash=3123191453

(bold: stderr; normal weight: stdout)

I will go ahead and add this Warning message as i feel that it has the consensus, @sftim can you please let me know which file location would be required to change inorder to display this warning Thanks

sftim commented 1 year ago

Sorry - I'm not actually someone who codes in Go very often.

k8s-triage-robot commented 1 year ago

This issue is labeled with priority/important-soon but has not been updated in over 90 days, and should be re-triaged. Important-soon issues must be staffed and worked on either currently, or very soon, ideally in time for the next release.

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/remove-triage accepted

kubernetes / kubectl

Improve default kubectl behavior when it doesn't know what cluster to talk to #1340