Manuel Simón Nóvoa
2.6 KiB
title
| title |
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| Troubleshooting Worker Nodes and Generic Components |
This section applies to every node as it includes components that run on nodes with any role.
Prerequisites
Since RKE2 and K3s utilize containerd as the container runtime, crictl serves as the primary tool for container management, replacing the Docker CLI. To allow crictl to communicate with containerd, you must configure your environment by exporting the following variables:
RKE2
export PATH=$PATH:/var/lib/rancher/rke2/bin/
export CRI_CONFIG_FILE=/var/lib/rancher/rke2/agent/etc/crictl.yaml
K3s
export PATH=$PATH:/usr/local/bin
export CRI_CONFIG_FILE=/var/lib/rancher/k3s/agent/etc/crictl.yaml
Check if the Components are Running
There are two specific components launched on nodes with the worker role:
kubeletkube-proxy
RKE2
The kubelet runs natively as part of the rke2-agent (or rke2-server) systemd process, while kube-proxy runs as a Static Pod managed by containerd.
Check the status of the kubelet via the agent service:
systemctl status rke2-agent
:::note
If you are checking a controlplane node, use systemctl status rke2-server instead.
:::
Check the status of kube-proxy using crictl:
crictl ps --name kube-proxy
Example output:
CONTAINER IMAGE CREATED STATE NAME ATTEMPT POD ID
26c7159abbcc rancher/hardened-kubernetes:v1.28.8-rke2r1-build20240404 3 hours ago Running kube-proxy 0 1a2b3c4d5e6f7
K3s
Both kubelet and kube-proxy run as embedded processes inside the k3s-agent (or k3s server) systemd service. There are no separate containers for them.
Check their status by checking the K3s service:
systemctl status k3s-agent
:::note
If you are checking a controlplane node, use systemctl status k3s instead.
:::
Component Logging
The logging of the components can contain information on what the problem could be.
RKE2
# kubelet logs are part of the systemd service
journalctl -u rke2-agent -f | grep -i "kubelet"
# kube-proxy logs are retrieved from containerd
crictl logs $(crictl ps --name kube-proxy -q)
K3s
# Both components log to the systemd service
journalctl -u k3s-agent -f | grep -iE "kubelet|kube-proxy"