Fix Debian 11 bullseye slow SSH login and sudo on LXC Proxmox

# If Debian 11 is ran on a LXC container (Proxmox), SSH login and sudo actions can be slow
# Check if in /var/log/auth.log the following messages 
Failed to activate service 'org.freedesktop.login1': timed out (service_start_timeout=25000ms)

-> Run  systemctl mask systemd-logind
-> Run pam-auth-update (and deselect Register user sessions in the systemd control group hierarchy)

So glad I stumbled on this... During my upgrades, I had let dpkg replace my custom sshd_config with the stock one, so get fooled into thinking it was related to that. This fixed it.

Edit:
For anyone looking to do the pam-auth-update in a non-interactive way.... Use this:
"pam-auth-update --remove systemd"

I've now encountered this because i have to use a privileged container with debian 12. Unfortunately, this solution here prevents things like systemctl poweroff from working.

Fortunately, L1Cafe's link offers a better solution:

Comment out session optional pam_systemd.so in /etc/pam.d/common-session

This seems to solve the issue while keeping systemd-logind intact (haven't done much testing though!)

it works, thank you

This fixed my problem, thank you.

It's not possible to enable nesting in privileged containers though.

It's possible to turn on nesting after container creation: CT |-> Options |-> Features |-> Edit

Thanks! 🤗

Basically there is no need to mask the systemd-logind service. Just turn on "nesting" in proxmox.

This worked. I had forgotten to turn this on when I created the LXC.

Thank you, man