Networking:
PC_A DeviceA connected to the g1 / 0/1; PC_B DeviceA connected to the g1 / 0/2; PC_C DeviceA connected to the G1 / 0 /. 3;
PC_D DeviceB connected to the g1 / 0/1; PC_E connection to DeviceB the g1 / 0/2; PC_F connected to DeviceB the G1 / 0 /. 3;
DeviceA the g1 / 0/1 belongs vlan10, g1 / 0/2 belongs vlan20, g1 / 0/3 belonging vlan30; g1 / 0 / 24 as trunk
DeviceB the g1 / 0/1 belongs vlan10, g1 / 0/2 belongs vlan20, g1 / 0/3 belonging vlan30; g1 / 0/24 as trunk
DeviceC the g1 / 0/23 is connected to DeviceA g1 of / 0/24; g1 / 0 /24 is connected to the DeviceB the g1 / 0/24
DeviceC the g1 / 0/23 and g1 / 0/24 are as trunk 
experimental steps:
. 1, DeviceA basic configuration
SYS
VLAN 10
Port G 1/0/1
VLAN 20 is
Port G 1/0/2
VLAN 30
Port G 1/0/3
Inter G 1/0/24
Port Link-type Trunk
Port VLAN All the permit Trunk
2, the basic configuration DeviceB same DeviceA
3, DeviceC basic configuration
SYS
Inter G RG 1/0/23 to 1/0/24
Port Link-type Trunk
Port VLAN All the permit Trunk
4, PC_A access PC_D found unreasonable
use dis vlan in DeviceC above you can only see vlan 1
5, turn MVRP function
#DeviceA arranged MVRP
MVRP Global enable
Inter G 1/0/24
MVRP enable
MVRP the same configuration #DeviceB DeviceA
#DeviceC配置MVRP
mvrp global enable
inter r g 1/0/23 to g 1/0/24
mvrp enable
6, another visit PC_D with PC_A, successfully accessed
using dis vlan can see in the above DeviceC vlan 10 20 30