"Incorrect username or password" when flashing Xavier

I have 3 Xaviers and have successfully flashed the first two via Manual Setup. The third has a previously installed OS on it and I would like to update it.

I am using the SDK Manager to flash it, have connected the included USB-c cable from the Xavier to my host machine, and (after running ifconfig enp0s20f0u2 192.168.55.100 on the host) am able to ping/SSH in to the Xavier from the host machine (ssh nvidia@192.168.55.1).

However, when running SDK Manager and going through the flash step with “Automatic Setup”, after entering either the default (nvidia/nvidia) credentials, or ones for a user I have created on the system, it hangs for a minute and then shows “Incorrect username or password.” I again have confirmed that from a terminal on the host machine, I can SSH to the machine with the same IP adress and credentials entered into the SDK Manager flash setup screen.

Snippet from the logs:

11:17:59 DEBUG : running command < [ `lsusb | grep -c "0955:"` -ne 1 ] >
11:17:59 ERROR : command terminated with error
11:17:59 INFO : Only one nvidia device detected, as expected.
11:17:59 DEBUG : running command < ip addr | grep 192.168.55.1 >
11:17:59 INFO : inet 192.168.55.100/24 brd 192.168.55.255 scope global enp0s20f0u2
11:17:59 INFO : command finished successfully
11:17:59 DEBUG : running command < nc -z -vv -w 5 192.168.55.1 22 >
11:17:59 INFO : Connection to 192.168.55.1 22 port [tcp/ssh] succeeded!
11:17:59 INFO : command finished successfully
11:17:59 INFO : Connection to the device via SSH is avaliable.
11:17:59 DEBUG : running command < ssh -F /dev/null -o PubkeyAuthentication=no -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -o ConnectTimeout=5 nvidia@192.168.55.1 echo hello >
11:18:00 INFO : Warning: Permanently added '192.168.55.1' (ECDSA) to the list of known hosts.
11:20:00 INFO : Password:
11:20:00 INFO :
11:20:00 INFO : Connection closed by 192.168.55.1 port 22
11:20:00 ERROR : command terminated with error
11:20:00 ERROR : Incorrect username or password.

Hi mdlh,

Using sdkmanager to flash Xavier, the first time boot up, please connect HDMI monitor to doing init process setup your username, password and timezone…, then you can use your setup username and password to login.

The Xavier was already set up with a username and password (the “user I have created on the system” in original post).

However, the system had had PAM and SSSD configured on the system that, even after uninstallation of these systems, has relevant lines in the /etc/ssh/sshd.conf file. Even though login via shell worked, for some reason the sdkmanager could not login with the same credentials. After removing all PAM lines from sshd.conf file, sdkmanager was able to login and proceed with flashing.