This object indicates the name of the latest saved
configuration file of the device. The file name is
consisted of the device host name, MAC address and
file extension 'REV2', for example
'SwitchA-0021.d7ae.fc00.REV2'. The file is stored in
the host indicated by the csiBackupHostUrl object.
If the device configuration file is saved again, .REV2
file is copied to .REV1, and .REV2 is over-written with
the latest device configuration.