Severe network fault on the unit recently, the network topology is shown in figure: , now from branch to office buildings, or from the office to branch will be the serious nestlings PING, PING basically 50 times will drop 20 times or so, time interval is not fixed, from 9306 in 13 different gateway is with 10.66.152 X's MAC address is the same, but in the unit at the next higher level for network management software, in addition to 10.66.152. X has a MAC address, other webmasters don't have the MAC address (0000-0000-0000), now is there any way, let the same port under the MAC address of gateway into different?