Ubuntu Server 20.04.2 LTS - Hangs After Bootup - cloud-init [1781]: YYYY-MM-DD HH:MM:SS,182 - cc_final_message.py[WARNING]: Used fallback datasource
I find I have the same issue but found out how to get the console working again. Press CTL-ALT-F2 and you'll get a working console. Interestingly enough, if you return to tty1 with CTL-ALT-F1 you also get a login prompt that works there too.