docker networking namespace not visible in ip netns list

Question

When I create a new docker container like with

docker run -it -m 560m --cpuset-cpus=1,2 ubuntu sleep 120

and check its namespaces, I can s

Answer 1

Similar but different with @jary’s answer.
There is no need to introduce /proc// or netster. Only one move below to achieve what you want. Thus, you could operate containers’ network namespace just like they are created manually on host machine.

One Move:

ln -s /var/run/docker/netns  /var/run/netns 

Result:

Start a container:

docker run -tid ubuntu:18.04 

List container:

root@Light-G:/var/run# docker ps
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
972909a27ea1        ubuntu:18.04        "/bin/bash"         19 seconds ago      Up 18 seconds                           peaceful_easley

List network namespace of this container:

root@Light-G:/var/run# ip netns list
733443afef58 (id: 0)

Delete container:

root@Light-G:/var/run# docker rm -f 972909a27ea1
972909a27ea1

List network namespace again:

root@Light-G:/var/run# ip netns list
root@Light-G:/var/run#