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 |