So I upgraded a CentOS 8 system to Rocky using the migrate script and all seemed OK, until I realized that logging in via ssh using password authentication stopped working. Private-key authentication continues to work OK.
Any ideas on what the problem could be?
sshd_config looks normal, rebooted the system after the upgrade and using su to change users via password works OK.
Figured it out with more debugging - I noticed by comparing to backups that /etc/pam.d/sshd had changed and the new version had the line
auth substack password-auth
missing from the top. There was also a sshd.prev file in the same folder that had the line. I copied /etc/pam.d/sshd.prev file over /etc/pam.d/sshd and things are working now. I wonder what changed the file?
The root cause was the fact that the JumpCloud agent (cloud directory that we use to manage systems) does not support Rocky Linux and it was breaking /etc/pam.d/sshd after the system migration.
So not a Rocky problem at all, but I assume that similar issues will arise when client software makes assumptions based on the OS name…