Oracle Message ORA-06268 - NETNTT: cannot read /etc/oratab

ERRORNETNTT: cannot read /etc/oratab
CAUSEThe NTT two-task driver could not read configuration information from /etc/oratab.
ACTIONMake sure /etc/oratab exists and is readable. This error may occur if the file is incorrectly formatted. It also may occur if the driver has run out of memory.