3Com S7906E Configuration Manual page 2173

Device A, Device B, Device C and Device D constitute RRPP domain 1, VLAN 4092 is the primary
control VLAN of RRPP domain 1, and RRPP domain 1 protects all the VLANs;
Device A, Device B, Device C and Device D constitute primary ring 1, and Device B, Device C and
Device E constitute subring 2;
Device A is the master node of primary ring 1, GigabitEthernet 2/0/1 is the primary port and
GigabitEthernet 2/0/2 is the secondary port;
Device E is the master node of subring 2, GigabitEthernet 2/0/1 is the primary port and
GigabitEthernet 2/0/2 is the secondary port;
Device B is the transit node of primary ring 1 and the edge node of subring 2, and GigabitEthernet
2/0/3 is the edge port;
Device C is the transit node of primary ring 1 and the assistant-edge node of subring 1, and
GigabitEthernet 2/0/3 is the edge port;
Device D is the transit node of primary ring 1, GigabitEthernet 2/0/1 is the primary port and
GigabitEthernet 2/0/2 is the secondary port.
Figure 1-9 Network diagram for intersecting rings configuration
Configuration procedure
1) Configuration on Device A
# Configure the suppression time of physical-link-state changes on GigabitEthernet 2/0/1 and
GigabitEthernet 2/0/2 as zero, disable STP, configure the two ports as trunk ports, and assign them to
all VLANs.
<DeviceA> system-view
[DeviceA] interface gigabitethernet 2/0/1
[DeviceA-GigabitEthernet2/0/1] link-delay 0
[DeviceA-GigabitEthernet2/0/1] undo stp enable
[DeviceA-GigabitEthernet2/0/1] port link-type trunk
[DeviceA-GigabitEthernet2/0/1] port trunk permit vlan all
[DeviceA-GigabitEthernet2/0/1] quit
[DeviceA] interface gigabitethernet 2/0/2
[DeviceA-GigabitEthernet2/0/2] link-delay 0
[DeviceA-GigabitEthernet2/0/2] undo stp enable
[DeviceA-GigabitEthernet2/0/2] port link-type trunk
[DeviceA-GigabitEthernet2/0/2] port trunk permit vlan all
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