Note: This issue is now fixed in DKP 2.2.1 and above.
Users who have deployed DKP 2.X in Flatcar Linux may notice that certain Grafana dashboards are empty, including stats related to CPU usage, Memory usage, Network usage, and Storage IO.
This is a known issue that is related to the directory location of the containerd socket which is different on Flatcar compared to other distributions of Linux.
Cadvisor is expecting the containerd socket to be located at /run/containerd/containerd.sock but in Flatcar it is located at /run/docker/libcontainerd/docker-containerd.sock.
Until this issue is addressed in the product, the current workaround is to create a symlink at this location.
On each node in the cluster, run:
ln -s /run/docker/libcontainerd/docker-containerd.sock /run/containerd/containerd.sock
After creating the symlink, restart the kubelet service:
systemctl restart kubelet
Please be aware that this workaround will not survive after a reboot of the node and must be performed again anytime the system restarts.