1146 CHAPTER 90: RRPP CONFIGURATION
edge node are up again. A temporary loop may arise in the data VLAN in this 
period. As a result, broadcast storm occurs.
To prevent temporary loops, non-master nodes block them immediately (and 
permits only the packets of the control VLAN) when they find their ports accessing 
the ring are up again. The blocked ports are activated only when the nodes ensure 
that no loop will be brought forth by these ports.
Broadcast storm suppression mechanism in a multi-homed sub ring in case 
of primary ring link failure
As shown in Figure 347, Ring 1 is the primary ring, and Ring 2 and Ring 3 are sub 
rings. When two links of the primary ring between the edge node and the 
assistant edge node are down, the master nodes of Ring 2 and Ring 3 will open 
their respective secondary ports, and thus a loop among B, C, E and F is 
generated. As a result, broadcast storm occurs.
In this case, to prevent from generating this loop, the edge node will block the 
edge port temporarily. The blocked edge port is activated only when the edge 
node ensures that no loop will be brought forth when the edge port is activated.
Protocols and Standards Related standard: RFC 3619.
RRPP Configuration 
Task List
Complete the following tasks to configure RRPP
c
CAUTION:
■ It is recommended to configure the primary ring first and then the sub ring 
when you configure an RRPP domain. Moreover, a Ring ID cannot be applied to 
more than one RRPP ring in one RRPP domain.
■ If a device lies on multiple RRPP rings in an RRPP domain, only one primary ring 
exists. The device serves as either an edge node or an assistant edge node on 
the sub rings.
■ The total number of rings configured on a device in all RRPP domains should 
not be greater than 16.
■ Modification of node mode, port role and ring level of an RRPP ring is 
prohibited after configuration. If needed, you must first delete the existing 
configuration.
■ The secondary port on the master node and a port on a sub ring node must 
not be configured as a multi-domain intersection common port, and the two 
ports that access the same node to the same RRPP ring must not be configured 
as multi-domain intersection common ports at the same time.
Task Description 
“Configuring Master Node” on page 1147  Required 
“Configuring Transit Node” on page 1148  Optional 
“Configuring Edge Node” on page 1149  Optional 
“Configuring Assistant Edge Node” on page 1151  Optional