Ubuntu 20.10 sssd (System Security Services Daemon) failure
Solution 1:
There are at least three possible fixes.
Fix #1:
Disable sssd from starting on systems where it's not needed.
sudo systemctl stop sssd
sudo systemctl disable sssd
Fix #2:
sudo cp /usr/lib/x86_64-linux-gnu/sssd/conf/sssd.conf /etc/sssd/.
sudo chmod 600 /etc/sssd/sssd.conf
sudo systemctl enable sssd
sudo systemctl start sssd
Source: https://ubuntuforums.org/showthread.php?t=2452209&p=13994052
Fix #3:
Properly configure sssd, using /etc/sssd/sssd.conf, to your site's specific needs. See man sssd.conf for more information.