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#k3s
Title
l

late-needle-80860

06/24/2022, 9:28 AM
I want to try out gRPC probes on v1.23.6 of k3s. But, I'm struggling with how to enable this alpha feature. Using the
kubelet-api-server-arg
parameter is not doing the job. Have anyone tried and successfully enabled the gRPC probe alpha feature on a k3s distribution? Thanks!!! 🙏
q

quick-dentist-45681

06/24/2022, 5:02 PM
I might be wrong, but I think I've read that all alpha-features are removed from the k3s binary to keep the size down or something like that.
l

late-needle-80860

06/24/2022, 5:03 PM
Hmm sad … fair enough
@creamy-pencil-82913 is that so?
c

creamy-pencil-82913

06/27/2022, 4:46 PM
kubelet-api-server-arg
is not a thing. Did you want
kubelet-arg
or perhaps
kube-apiserver-arg
?
l

late-needle-80860

06/27/2022, 7:43 PM
Sorry … I did use
kube-apiserver-arg
and not
kubelet-api-server-arg
- still no cigar though @creamy-pencil-82913 - I’m not getting
gRPC
enabled?
I’ve been trying to read the docs thoroughly. However, I can’t quite decipher whether this a per Kubernetes system component thing or not. The cluster where I’m trying this, being a v1.23.6 should do it. However, I’m not 100% on how I enable alpha features. Thank you
c

creamy-pencil-82913

06/27/2022, 8:56 PM
what exactly did you try?
l

late-needle-80860

06/28/2022, 8:08 AM
See loc 165
That's what I tried
@creamy-pencil-82913 does that make sense?
c

creamy-pencil-82913

06/28/2022, 6:05 PM
the kubelet is what does the actual probing, so you probably need to enable the feature-gate there as well. Have you done so?
the Kubernetes docs don’t ever tell you which components need a particular feature-gate, so if something’s not working right it’s usually best to enable it on all of them (apiserver, controller-manager, scheduler, kubelet) until you can figure out which ones actually need it.
l

late-needle-80860

06/28/2022, 6:10 PM
Aah right - thank you! Pretty complex to figure this out then
Nope I haven’t enabled it on the kubelet - how do I do so for
k3s
thanks
@creamy-pencil-82913 do you know mate? Thanks!
c

creamy-pencil-82913

06/29/2022, 12:02 AM
I told you how up above
Did you want
kubelet-arg
or perhaps
kube-apiserver-arg
l

late-needle-80860

06/29/2022, 7:39 AM
Hmm okay fair. Just added a pic. Where I showed what I'm doing. Today I'm using kube-apiserver-arg
So I've tried with all these arguments now. However, these are only configured on control-plane nodes so when a gRPC probe test workload goes to a worker it doesn't work. If I make the workload tolerate the control-plane taint and cordon all workers the workload goes to X control-plane node and it works. So I need to configure the kubelet I guess? At least it's the only K3s/Kubernetes arg. That makes sense in this context. Am I right?
c

creamy-pencil-82913

07/01/2022, 5:08 PM
yes, you need to enable the feature-gate on all the components that use it
l

late-needle-80860

07/01/2022, 6:10 PM
Alright. Thank you! Trying …. really requires some investigation this alpha feature thingy
So gRPC probes can be had on k3s workers with the use of the
kubelet-arg
parameter.
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