docker.service in Ubuntu is agnostic to user's environment variables, but if it were to be passed to the
docker.service itself, then it works.
I got it working by adding the following line to the
/lib/systemd/system/docker.service file, right before
docker.service file looked like this:
Description=Docker Application Container Engine
After=network-online.target firewalld.service containerd.service
# the default is not to use systemd for cgroups because the delegate issues still
# exists and systemd currently does not support the cgroup feature set required
# for containers run by docker
ExecStart=/usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock
ExecReload=/bin/kill -s HUP $MAINPID
# Note that StartLimit* options were moved from "Service" to "Unit" in systemd 229.
# Both the old, and new location are accepted by systemd 229 and up, so using the old location
# to make them work for either version of systemd.
# Note that StartLimitInterval was renamed to StartLimitIntervalSec in systemd 230.
# Both the old, and new name are accepted by systemd 230 and up, so using the old name to make
# this option work for either version of systemd.
# Having non-zero Limit*s causes performance problems due to accounting overhead
# in the kernel. We recommend using cgroups to do container-local accounting.
# Comment TasksMax if your systemd version does not support it.
# Only systemd 226 and above support this option.
# set delegate yes so that systemd does not reset the cgroups of docker containers
# kill only the docker process, not all processes in the cgroup
This seems to have fixed the problem for me and it is working on Ubuntu 20.04.