The value of tmnxVrrpOperStandbyFwding specifies
whether this vrrp instance allows forwarding packets to
standy router.
The value 'false' specifies that a standby router should
not forward traffic sent to virtual router's MAC address.
However, the standby router should forward traffic sent
to the standby routers real MAC address.
The value 'true' specifies that a standby router should
forward all traffic.