Since Focal is “oldstable LTS” and Jammy “stable LTS” it seems reasonable for Whonix to only support the latest stable LTS (and perhaps other, higher, stable non-TLS versoins, if any).
Also quote Whonix wiki VirtualBox - manual installation:
Tested on October 2022 using Ubuntu version 22.04. Older versions are not recommended.
Also due to the requirement of a recent VirtualBox version, support for Ubuntu versions lower than Jammy (22.04) (LTS) won’t be provided.
Alternatives may or may not be functional on that Ubuntu version that could maybe be used meanwhile:
B) Whonix Linux Installer using onion instead of TLS. (Since that doesn’t require rsync-ssl.) Use the “onion” tab on that wiki page.
Whonix Installation might not be the issue but the VirtualBox version might be too low. So probably not worth bothering.
In short: Your host operating system version is too old.
Planned changes:
Wel’ll update the Whonix Linux installer - if a Ubuntu host operating system has been detected to require minimum version 22.04 or otherwise show an error message.
Sorry for your experience, I also too wish the script would also work. It is tested on Debian/Kicksecure/Whonix, Ubuntu is only through automated actions so it is not a system I log in.
We evaluated curl, wget and rsync. Rsync was chosen because it can continue writing to a file that failed download before, making it better for big files such as the VM images and low bandwidth connections when using the Tor network.
Rsync-ssl is needed because rsync by itself does not handle TLS/SSL.
This would violate one of the pillars of the script, which is to use a secure connection, via TLS of via onion (onion does not requires certificates).
Please report the logs from your installation and your Ubuntu version. If you could post the output of: