The ITCM uses below command to fetch serial number.
/usr/platform/`uname -i`/sbin/eeprom | grep ChassisSerialNumber | grep -v 'data not available'
Here are more details regarding the above command.
* SUN provides sneep tool to store the chassis serial number in EEPROM
* The administrater would have to look at the back of the machine, note the number,
* and type "sneep -s $serial_number"
* The info is then appeared in EEPROM as:
* nvramrc=." ChassisSerialNumber 83EF7FB5 " cr
* which can be extracted with
* "eeprom -v | grep ChassisSerialNumber"