CODEWITHSUNDEEP
dockerkernelkernel-module
user4725754
user4725754

Reputation:

Docker loading kernel modules

I tried to install a kernel module, xfsprogs. It was successfully installed inside a container. It is really surprising, but lsmod doesn't list this module inside container or in the host system. How can a new kernel module loaded in a container?(CentOS container, Ubuntu host)

Upvotes: 24

Views: 56700

Answers (3)

Tinkaal Gogoi
Tinkaal Gogoi

Reputation: 4898

In Linux host:

  • Run the container in privileged mode: --privileged
  • Add all capabilities: --cap-add=ALL
  • mount host /lib/modules into the container: -v /lib/modules:/lib/modules
docker run --name container_name \
           --privileged \
           --cap-add=ALL -d \
           -v /dev:/dev \
           -v /lib/modules:/lib/modules \
           image_id

Caution: Here all Linux capabilities are added so capabilities can be refined. Few words about Linux capabilities Model

Upvotes: 35

Edward Anderson
Edward Anderson

Reputation: 13926

Falco is an example of a container that loads a kernel module as part of its start process.

docker run -i -t --name falco --privileged \
  -v /var/run/docker.sock:/host/var/run/docker.sock \
  -v /dev:/host/dev \
  -v /proc:/host/proc:ro \
  -v /boot:/host/boot:ro \
  -v /lib/modules:/host/lib/modules:ro \
  -v /usr:/host/usr:ro \
  sysdig/falco

Upvotes: 6

askb
askb

Reputation: 6786

Containers interact with the kernel through system calls and don't include any part of the kernel or the kernel modules inside the container. This is one of the reasons why containers designed to be light weight and portable. Also xfsprogs are user space programs and not kernel modules.

How can a new kernel module loaded in a container?(CentOS container, Ubuntu host)

The module needs to be loaded on your host OS, and not from the docker container.

Upvotes: 21

Related Questions