After an upgrade
sshd|plinth|fail2ban services are unavailable.
On https://freedombox/_cockpit/system/services at many processes:
Unit
plinth.serviceis masked.
sshd.service is masked.
Failed to restart fail2ban.service: Unit fail2ban.service is masked.
Using https://freedombox/_cockpit/system/terminal
ournalctl -b 0 -u plinth have no data and systemctl unmask|enable|start commands have no desired result
As @Sunil revealed in a topic before
‘freedombox’ package can be removed during the upgrade process
The solution
apt install freedombox