sometimes you just want a bare ubuntu in a container to ssh to

entrypoint.bash

v/entrypoint.bash 
#!/bin/bash
#!/bin/bash

# sudo docker run "--env=SSH_KEY=$( ssh-add -L )" --name ssh1 --volume=$HOME/ssh1:/v '--entrypoint=/v/entrypoint.bash' -d ubuntu:20.04

mount -t devtmpfs none /dev
mount -t devpts   none /dev/pts


apt update
apt install -y openssh-server

(cd; umask 077 ; mkdir -p .ssh && echo "$SSH_KEY" >> .ssh/authorized_keys; )

mkdir -p /run/sshd
/usr/sbin/sshd
echo "ASDF"
sleep 99999999999
bash