adding this config to kubelet on RKE2 cluster

[thinzaung81]

I already have RKE2 cluster up and running already. I wanted to add this configuration image-gc-high-threshold to my kubelet so that it will clean up the images/continer automatically. Is there a way I can do it? Do I just add it to config.yaml file ?

Thanks

[brandond]

yep. and restart.

[brandond]

I'm not sure what you mean by "wrapping" the cluster. RKE2 is a Kubernetes distribution. It contains all the normal Kubernetes components built directly from upstream Kubernetes project code, including the kubelet. We do not override or alter the kubelet's default image GC thresholds. You can check the rke2 service logs in journald, or look at the process list, to see what args we do start the kubelet with.

CLI flag deprecation does not mean that the flags no longer work. They still work fine, and have the documented defaults.

[nookseal]

For wrapping I refer to your message below just for reference that we use Rancher to manage kubernetes.

"if you're using Rancher you should add the Kubelet args via Rancher, not by poking at the nodes directly"

So let say if I want to adjust some kubelet-args, image-gc-high-threshold=70 and image-gc-low-threshold=50.
I've found so many way on the other website and discussion and not sure what is the correct way.

actually there is /etc/rancher/rke2/config.yaml.d/50-rancher.yaml but as I understand we don't touch this

so we create new file in /etc/rancher/rke2/config.yaml.d/kubelet-extra-args.yaml

kubelet-arg:

• "image-gc-high-threshold=70"
• "image-gc-low-threshold=50"
• "maximum-dead-containers=10"
• "maximum-dead-containers-per-container=2"

then restart rke2-agent service on each worker

not sure if this is correct way?

[brandond]

No. You go into Rancher, edit the cluster there, and add the desired kubelet args.

[nookseal]

I've tried looking the Rancher GUI -> CLuster Management
try checking Edit as yaml, edit config but seem not found any option related to the extra-args for Kubernetes component related

Also, try checking the ps command for kubelet and found many parameter running on kubelet process including --cluster-dns, --eviction-hard, --eviction-minimum-reclaim

but not found parameter with image-gc low and high on the ps command output, normally it's run as default if not specify anything?

will try checking more.

[brandond]

Where exactly were you looking in the Rancher UI?