The name of the ASCII configuration file to be
used by the device to boot.
* If a NULL string is passed, that signifies
the switch will be booted up using the conventional
mpm.cnf file in the flash;
** If a non-NULL string is passed in, and the file is
present on the device, then the switch/device will
booted up in the cache-only mode, *and* the
specified will be used to boot up the device.