Step 1.) Upgrade to Debian 11 first
The process to go to Debian 12 is not as smooth as 11, when trying to upgrade from Debian 10. In fact, it doesn't work directly, so you'll first need to follow this guide to update to Debian 11, reboot and come back here if successful.
Step 2.) Update sources.list
Update your /etc/apt/sources.list like this:
deb http://........
The issue is that Docker images are stripped down, so many tools and even python3 is missing, so you'll have to build or update the actual image yourself.
I assume you have started an image with something like this and that you have the Nvidia Toolkit installed (assuming you are using GPUs). If you're not using nvidia just remove --runtime=nvidia --gpus all.
docker run -it --runtime=nvidia --gpus all ubuntu bash
These works for most images li........
The Xen VPSI had was not working properly and when they asked for the login information I found the support was coming directly from India:
whois 122.178.148.*
[Querying whois.apnic.net]
[whois.apnic.net]
% [whois.apnic.net node-5]
% Whois data copyright terms http://www.apnic.net/db/dbcopyright.html
inetnum: 122.178.128.0 - 122.178.191.255
netname:&........