There are sufficient articles teaching ppl how to access guest machine via ssh in virtualbox, while it takes me time to figure out the reverse way. It is very important since i dont that trust virtual machine and i hope to do the one-way backup of my work in the host.
Well, here is the answer. If using NAT, the ip address 10.0.2.2 is the host machine.
Note: remember to add “sshd: 127.0.0.1” in /etc/hosts.allow otherwise the sshd gives u “ssh_exchange_identification: connection closed by remote host” error.