You'll not be able to directly login your guest virtual machine in
RDP if it's under
NAT network. You'll have to configure port forwarding to access your guest VM in Virtualbox as detailed below;
In this example, port
2202 in the host machine will forward to port
22 of the guest machine whereby
10.0.2.15 is the default
IP for guest
Host IP field blank will default to
Guest IP defaults to whatever the IP address is assigned to the guest VM.
user@host:~ $ ssh -p2222 email@example.com Warning: Permanently added '[127.0.0.1]:2222' (ECDSA) to the list of known hosts. firstname.lastname@example.org's password: Welcome to Ubuntu 18.04 LTS (GNU/Linux 4.15.0-20-generic x86_64) * Documentation: https://help.ubuntu.com * Management: https://landscape.canonical.com * Support: https://ubuntu.com/advantage System information as of Wed Sep 5 16:52:59 +08 2018 System load: 0.0 Processes: 91 Usage of /: 18.8% of 8.80GB Users logged in: 1 Memory usage: 6% IP address for enp0s3: 10.0.2.15 Swap usage: 0% 138 packages can be updated. 72 updates are security updates. Last login: Wed Sep 5 16:47:16 2018 from 10.0.2.2 To run a command as administrator (user "root"), use "sudo <command>". See "man sudo_root" for details. user@host:~$
SSH is used to test the forwarding rule as
SSH is listening on port
22 of the guest VM.