During login, file system full errors are seen and the login fails with the message No utmpx entry.
This error is caused by a full file system. The system has no space to write its utmpx (login information) entry.
To correct this condition the system must be booted into single user mode. Then clear (do not delete) these files: /var/adm/utmp and /var/adm/utmpx. This can be done by typing:
#cat /dev/null > /var/adm/utmp #cat /dev/null > /var/adm/utmpx
In some cases, after clearing these files, the /var file system might still be full. In this case type:
du -askd /var |sort -nr |more