There was a HW issue that rebooted several virtual machines and one of them had the following problem: from that point the server isn't reachable via network (ssh) because it gives error message:
We tried to log in via console, but if we type any username in, it gives:
Error message. Interesting thing that sshd_config has "UsePam No" -> maybe it is not a PAM problem?
We can only enter single user mode with replacing the "ro" to "rw init=/sysroot/bin/sh" at the line in linux16, CTRL+X, then chroot /sysroot.
Question: What should we check when we are in single user mode?
We already restored the "system-auth-ac" and "password-auth-ac", the same error message after reboot.
Another interesting thing is that when we are in single user mode, after chroot, the "/var/log" doesn't exists. There is no lvs command in chroot, but if we exit from chroot, and type lvs, there is only the root LV. Where are the other LVs?