SLES Server Login Error 15 SP4: Sorry, password authentication didn't work, please try again

Hello everyone, please can you help me with an error of access to a SLES 14 SP4 server which at the time of entering any local administration user generates the following error: Sorry, password authentication didn’t work, please try again.

In addition to this, when I restart the server, a message appears at the top of the screen: The volume “filesystem root” has only 0 bytes disk space.

How can we fix this error, the server had been working successfully with active directory authentication with PBIS for more than 40 days.

Sounds like your root filesystem is full, preventing the login due some (tmp) file not being created.