services.openssh = {
    enable = true;
    settings = {
      PermitRootLogin = "no";
      PasswordAuthentication = false;
      PubkeyAuthentication = true;
      MaxAuthTries = 3;
      ClientAliveInterval = 300;
      ClientAliveCountMax = 2;
    };
    allowSFTP = false;
  };

~/universe〉nixos-rebuild test --flake .#picard --target-host ccr@localhost --sudo
warning: Git tree '/home/ccr/universe' is dirty
building the system configuration...
warning: Git tree '/home/ccr/universe' is dirty
copying 0 paths...
sudo: Authentication failed, try again.
sudo: Authentication failed, try again.
sudo-rs: Maximum 3 incorrect authentication attempts
error: while running command with remote sudo, did you forget to use --ask-sudo-password?
Command 'ssh -o ControlMaster=auto -o ControlPath=/tmp/nixos-rebuild.4f0kmveu/ssh-%n -o ControlPersist=60 ccr@localhost -- sudo env NIXOS_INSTALL_BOOTLOADER=0 systemd-run -E LOCALE_ARCHIVE -E NIXOS_INSTALL_BOOTLOADER --collect --no-ask-password --pipe --quiet --service-type=exec --unit=nixos-rebuild-switch-to-configuration /nix/store/fmg4q127q3xwxlc74bnblmnv4cvslwv8-nixos-system-picard-25.11.20251031.2fb006b/bin/switch-to-configuration test' returned non-zero exit status 1.

[08:56:26.896 UTC] [x71c9@i7-nix-xps:~/.nx] [flakes]
└ $ nixos-rebuild switch --flake .#n97-nix-od40 --target-host x71c9@192.168.1.178 --use-remote-sudo
building the system configuration...
copying 0 paths...
[sudo] password for x71c9:
Shared connection to 192.168.1.178 closed.
[sudo] password for x71c9:
Sorry, try again.
[sudo] password for x71c9:
Shared connection to 192.168.1.178 closed.
[sudo] password for x71c9:
activating the configuration...
setting up /etc...
reloading user units for x71c9...
restarting sysinit-reactivation.target
Shared connection to 192.168.1.178 closed.
Done. The new configuration is /nix/store/3kcgk1x89y77sw0yfhp0akb79glj35nc-nixos-system-n97-nix-od40-25.05.20251027.daf6dc4

  users.users.<username> = {
    isNormalUser = true;
    extraGroups = [ "wheel" ];
    initialPassword = "password123";
    openssh.authorizedKeys.keys = [
      "<chiave>"
    ];
  };

In reply to Andrea Ciceri
Non ho esperienza a riguardo. Pero', per curiosita', quando booti la live funziona lo schermo?

In reply to Giacomo Debidda
Non sono sicuro di aver capito cosa intendi con live. Lo schermo principale del laptop lo vedo tranquillamente. I driver DisplayLink mi servono per un monitor esterno.

2 anni fa usavo Xubuntu e quei driver funzionavano.

Su NixOS non so se devo aggiungere un kernel module, una configurazione extra per il systemd service menzionato dalla guida.

In reply to Giacomo Debidda
Sisì, uso nixos da un paio d'anni ormai