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Problem with docker KERNEL , CPU realtime schedule and cgroup blkio weight, cgroup blkio weight_device

hi every one,

I Have install docker version → Server Version: 20.10.8 on ubuntu Ubuntu 21.04 y my problem is :

" level=warning msg=“Your kernel does not support CPU realtime scheduler”
" level=warning msg=“Your kernel does not support cgroup blkio weight”
" level=warning msg=“Your kernel does not support cgroup blkio weight_device”

how can I solve that ?

Regards,
Peter.

It would be easier to help if we knew what command you try to use or which Docker image. Since I had no idea what this error message was, I searched for the first error message on Google and found this:

Some commands require additional capabilities so it might be your problem as well.

the command I use is → sudo systemctl status docker :
Active: active (running) , but with that:
dockerd[25782]: time=“2021-12-23T13:53:16.879854648Z” level=warning msg=“Your kernel does not support CPU realtime scheduler”
dockerd[25782]: time=“2021-12-23T13:53:16.879879993Z” level=warning msg=“Your kernel does not support cgroup blkio weight”
dockerd[25782]: time=“2021-12-23T13:53:16.879886890Z” level=warning msg=“Your kernel does not support cgroup blkio weight_device”
dockerd[25782]: time=“2021-12-23T13:53:16.880047414Z” level=info msg=“Loading containers: start.”

I have tried with the link that you have put me but it remains the same

→ docker info

Client:
Context: default
Debug Mode: false
Plugins:
app: Docker App (Docker Inc., v0.9.1-beta3)
buildx: Build with BuildKit (Docker Inc., v0.6.1-docker)
scan: Docker Scan (Docker Inc., v0.12.0)

Server:
Containers: 0
Running: 0
Paused: 0
Stopped: 0
Images: 0
Server Version: 20.10.8
Storage Driver: overlay2

I meant the command in the container which requires these features (if you can share that). I assume you have containers not just the docker daemon after the installation.

Can you show how you tried?

The question is: do you just want to get rid of the warnings?
Or is it a blocker because something you need to run doesn’t work because of the missing kernel features?

That is a good question too :slight_smile:

Btw. there is a preflight check for docker that provides hints about which kernel modules need to be enabled for which functionality: https://raw.githubusercontent.com/moby/moby/master/contrib/check-config.sh

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