I’ve got kubelet message on our Kubernetes, the error message like below.
skipping pod synchronization - [PLEG is not healthy: pleg was last seen active 3m6.527452257s ago; threshold is 3m0s]
you can get the message from the rancher UI if using it.
![how to fix PLEG problem in Kubernetes 1 image 1](https://www.gosysops.com/wp-content/uploads/2021/11/image-1-1024x290.png)
Solution
According to the IBM document, this issue is caused by slow interaction between kubelet and Docker. the solution is to increase house-keeping
interval, house-keeping is the kubelet evaluates eviction thresholds based on its configured housekeeping-interval
which defaults to 10s
.
Step
We are using RKE to deploy Kubernetes, so all components are running in the form of containers. use docker inspect kubelet
` to see the configuration. no house-keeping argument in the below screenshot.
if your kubelet running as a service, you can modify
/etc/systemd/system/kubelet.service
![how to fix PLEG problem in Kubernetes 2 image](https://www.gosysops.com/wp-content/uploads/2021/11/image-1024x441.png)
To update kubelet, add the house-keeping
in the cluster.yml
![how to fix PLEG problem in Kubernetes 3 image 2](https://www.gosysops.com/wp-content/uploads/2021/11/image-2-1024x703.png)
To update the argument, run the below command
rke up --config cluster.yml
![how to fix PLEG problem in Kubernetes 4 image 3](https://www.gosysops.com/wp-content/uploads/2021/11/image-3-1024x213.png)
Verify
use docker inspect command to check again, house-keeping is added after updating.
![how to fix PLEG problem in Kubernetes 5 image 4](https://www.gosysops.com/wp-content/uploads/2021/11/image-4-1024x423.png)
Conclusion
“PLGE is not healthy” can happen due to various causes, I believe there are many potential causes I have not run into it. yet. this post provides one of the solutions to fix.