The serial-number command adds the serial number of a device to a PKI entity.
The undo serial-number command restores the default setting.
By default, the serial number of a device is not added to a PKI entity.
The parameters of a PKI entity include the identity information of the PKI entity. The CA identifies a certificate applicant based on identity information provided by a PKI entity. To further identify the applicant, add the serial number of the device to the PKI entity.
After the serial number of the device is added to a PKI entity, the certificate request packet sent by the device to the CA server carries this serial number. After receiving the certificate request packet, the CA server verifies the packet. For each valid packet, the CA server generates a digital certificate carrying the device serial number.