Dell M6220 User Configuration Manual page 1229

Figure 43-41. Add Candidate RP
3 Select the VLAN interface for which the Candidate RP is to be configured.
4 Enter the group address transmitted in Candidate-RP-Advertisements.
5 Enter the prefix length transmitted in Candidate-RP-Advertisements to
fully identify the scope of the group which the router supports if elected as
a Rendezvous Point.
6 Click Apply Changes.
The new Candidate RP is added, and the device is updated.
Managing IPv4 and IPv6 Multicast
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