Não há - a menos que você o insira manualmente na EEPROM usando sneep :
Oracle Serial Number in EEPROM (SNEEP) provides a software-accessible Chassis Serial Number (CSN) for all Oracle Solaris hardware platforms.
SNEEP uses the system EEPROM for persistent storage of the Chassis Serial Number and other important user-defined data such as asset information, contract ID, or the serial numbers of attached storage devices.
The presence of the software-accessible serial number and other service-related information can significantly simplify activities related to system service and asset management.
Without SNEEP, only a subset of the Solaris-based hardware platforms have a mechanism to maintain a software-accessible serial number. Among those platforms, there is a wide variety of mechanisms for this, making consistent access to this information difficult.
SNEEP provides one simple and consistent interface to the management of this information on all Solaris hosts, domains, and zones. SNEEP can also reference and maintain the serial number in the configuration files for the Oracle Explorer Data Collector.
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If your hardware includes the serial number in its EEPROM, then you can view it with the following command:
sneep -t hostname,serial,model
If your hardware does not already store the serial number in EEPROM, then you can use SNEEP to include it.
You will need to first obtain the serial number and manually enter it into EEPROM.
(minha ênfase)
On most Sun hardware, the serial number is always located on a physical tag somewhere on the machine. The Sun System Handbook tells exactly where to find it for all Sun machines. The handbook can be accessed at My Oracle Support (click the Knowledge tab and then select Sun System Handbook in the left-hand navigation): https://support.oracle.com
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WARNING:
The decimal number reported in the SPARC boot banner as the serial number when the machine is powered on is NOT the true serial number - it is the decimal form of the "host id". The host id is ordinarily seen in hexadecimal as the output of the Solaris hostid command.