Dell M6220 User Configuration Manual page 1231

Figure 43-43. Add Static RP
3 Enter the IP address of the RP for the group range.
4 Enter the group address of the RP.
5 Enter the group mask of the RP.
6 Check the Override option to configure the static RP to override the
dynamic (candidate) RPs learned for same group ranges.
7 Click Apply.
The new Static RP is added, and the device is updated.
Managing IPv4 and IPv6 Multicast
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