kubelet启动失败：/usr/bin/kubelet文件不存在的问题求助

Hey there! I totally get how frustrating it is when kubelet refuses to run even after a full reinstall—let's work through this step by step to get it sorted out.

First, let's look at the systemctl status you shared, which shows kubelet is stuck in an auto-restart loop with exit code 1:

ismail@Ismail:~/cloud_monitoringapp$ sudo systemctl status kubelet
● kubelet.service - kubelet: The Kubernetes Node Agent
     Loaded: loaded (/lib/systemd/system/kubelet.service; enabled; vendor preset: enabled)
    Drop-In: /usr/lib/systemd/system/kubelet.service.d
             └─10-kubeadm.conf
     Active: activating (auto-restart) (Result: exit-code) since Mon 2024-05-20 02:11:16 CEST; 4s ago
       Docs: https://kubernetes.io/docs/
    Process: 25239 ExecStart=/usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_CONFIG_ARGS $KUBELET_KUBEADM_ARGS $KUBELET_EXTRA_ARGS (code=exited, status=1/FAILURE)
   Main PID: 25239 (code=exited, status=1/FAILURE)
        CPU: 55ms

Since you've already tried reinstalling, let's dig into the most likely culprits:

1. Verify the kubelet binary exists and is executable #

Exit code 1 can sometimes mean the binary itself is missing or corrupted. Run this command to check:

ls -l /usr/bin/kubelet

• If the file isn't listed, your reinstall didn't complete successfully. We'll need to do a thorough cleanup and reinstall again (see step 3 below).
• If it exists, double-check its executable permissions with sudo chmod +x /usr/bin/kubelet just in case it lost access rights during reinstall.

2. Check for detailed error messages in journalctl #

The snippet you shared from journalctl -u kubelet cuts off, but the full log will have the exact reason kubelet is failing. Run this to stream real-time logs as kubelet tries to start:

sudo journalctl -u kubelet -f

Look for lines marked with ERROR or Failed—these will point you to specific issues like missing config files, invalid kubeconfig entries, port conflicts, or dependency problems.

3. Perform a complete Kubernetes cleanup and reinstall #

If the binary is missing or logs point to corrupted files, let's wipe everything clean before reinstalling:

# Purge all Kubernetes packages
sudo apt-get purge -y kubeadm kubectl kubelet kubernetes-cni kube*
# Remove leftover dependencies
sudo apt-get autoremove -y
# Delete config and data directories
sudo rm -rf ~/.kube
sudo rm -rf /etc/kubernetes
sudo rm -rf /var/lib/kubelet
sudo rm -rf /var/lib/etcd
# Reload systemd to clear old service definitions
sudo systemctl daemon-reload

Then reinstall using the official Kubernetes repo (adjust the version if you need a specific one):

# Install prerequisites
sudo apt-get update && sudo apt-get install -y apt-transport-https ca-certificates curl
# Add Kubernetes GPG key
curl -fsSL https://pkgs.k8s.io/core:/stable:/v1.30/deb/Release.key | sudo gpg --dearmor -o /etc/apt/keyrings/kubernetes-apt-keyring.gpg
# Add Kubernetes repo
echo 'deb [signed-by=/etc/apt/keyrings/kubernetes-apt-keyring.gpg] https://pkgs.k8s.io/core:/stable:/v1.30/deb/ /' | sudo tee /etc/apt/sources.list.d/kubernetes.list
# Update and install packages
sudo apt-get update
sudo apt-get install -y kubelet kubeadm kubectl
# Hold packages to prevent automatic updates
sudo apt-mark hold kubelet kubeadm kubectl

4. Check system environment issues #

Sometimes system settings can block kubelet:

• AppArmor (Ubuntu): Make sure it's not interfering. You can temporarily disable it with sudo systemctl stop apparmor and try starting kubelet again.
• Firewall rules: Ensure ports used by kubelet (like 10250) are open. You can temporarily disable the firewall to test: sudo ufw disable (remember to re-enable it later if this fixes the issue).
• Kernel compatibility: Verify your system kernel meets Kubernetes requirements (Ubuntu 22.04 recommends kernel 5.4+). Run uname -r to check.

Once you've tried these steps, share the detailed error logs from journalctl if you're still stuck—I can help you parse them further!

备注：内容来源于stack exchange，提问作者Nazim Razac