I'm running Debian Buster and while I was upgrading qemu-extra-blocks, it brought up the usual sshd_config reconfiguration screen (in my SSH terminal) saying that a new version of the sshd_config file is to be installed and either I proceed with it or keep the local file that's currently being used. I accidentally pressed Esc and it just continued with the installation. Immediately after pressing Esc, here's what I saw:

Setting up openssh-server (1:8.4p1-2~bpo10+1) ...
Installing new version of config file /etc/init.d/ssh ...
Installing new version of config file /etc/ssh/moduli ...
rescue-ssh.target is a disabled or a static unit, not starting it.

I'm a Linux noob and I'm not sure if that did something negative to my system? Is pressing Esc the same as choosing "keep the local file..."?

I restarted the server and tried ssh'ing again. What I noticed is that after I input my user password, it takes more than a minute for it to get in and when I do a systemctl status I see a degraded status with this failed units:

● user@1000.service loaded failed failed User Manager for UID 1000

It does look like something went wrong with the upgrade, bummer. Any ideas?

root@nuc:~# systemctl status user@1000.service
● user@1000.service - User Manager for UID 1000
Loaded: loaded (/lib/systemd/system/user@.service; static)
Active: failed (Result: exit-code) since Thu 2021-05-06 00:38:06 PST; 22min ago
Docs: man:user@.service(5)
Main PID: 3319 (code=exited, status=1/FAILURE)
CPU: 37ms

May 06 00:36:36 nuc systemd[3324]: gpgconf: error running '/usr/lib/gnupg/scdaemon': probably not installed
May 06 00:38:06 nuc systemd[1]: user@1000.service: Main process exited, code=exited, status=1/FAILURE
May 06 00:38:06 nuc systemd[1]: user@1000.service: Killing process 3324 (gpgconf) with signal SIGKILL.
May 06 00:38:06 nuc systemd[1]: user@1000.service: Killing process 3325 (awk) with signal SIGKILL.
May 06 00:38:06 nuc systemd[1]: user@1000.service: Killing process 3330 (dirmngr) with signal SIGKILL.
May 06 00:38:06 nuc systemd[1]: user@1000.service: Killing process 3325 (awk) with signal SIGKILL.
May 06 00:38:06 nuc systemd[1]: user@1000.service: Killing process 3330 (dirmngr) with signal SIGKILL.
May 06 00:38:06 nuc systemd[1]: user@1000.service: Failed with result 'exit-code'.
May 06 00:38:06 nuc systemd[1]: user@1000.service: Unit process 3330 (dirmngr) remains running after unit stopped.
May 06 00:38:06 nuc systemd[1]: Failed to start User Manager for UID 1000.

Installing scdaemon fixed the issue. The cause was because I accidentally did an upgrade of a lot of packages from backports including gnpgconf.