I just installed Ubuntu Server 20.04 on an old HP PC (AMD Phenom II quad-core with 8GB RAM and large hdd). After realizing I needed wired internet to configure WLAN, I dutifully broke out the obligatory, decade-old, unused ethernet cable and got to work.
I did some research here and elsewhere, and made adjustments to netplan using my .yaml. 500 indentation issues later, I finally got sudo netplan apply to shut up after hitting enter.
“$ ip a” showed address for ethernet, but WLAN returns “<NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000 link/ether xx:xx:xx:xx:xx:xx brd ff:ff:ff:ff:ff:ff” where “xx:…” is a bunch of random numbers/letters and “ff:…” is actually “ff:…”.
No wireless connectivity. I have not tried to connect wirelessly after reboot yet. I believe my system time/date is correct.
[EDIT]: Adding info almost immediately after posting - I did install wpasupplicant. Also, I don’t know how to do the whole box with code thing to show you the edits I made to *.yaml, but I spent a lot of time trying to learn how to do it correctly on netplan.io, which is really not that helpful for what I was attempting. Also - I just tried to connect wirelessly after reboot and no luck.