HP A6600 Configuration Manual page 232

Establishing share-MDT in a PIM-DM network
Figure 66 Share-MDT establishment in a PIM-DM network
As shown in 0, PIM-DM is enabled in the network and all the PE devices support VPN instance A. The
process of establishing a share-MDT is as follows:
The public network on PE 1 initiates a flood-prune process in the entire public network, with the BGP
interface address (namely the interface address used to establish the BGP peer) as the multicast source
address and the share-group address as the multicast group address. All the other PE devices that are
running VPN instance A are group members, so that a (11.1.1.1, 239.1.1.1) state entry is created on
each device along the path in the public network. This forms an SPT with PE 1 as the root, and PE 2 and
PE 3 as leaves.
At the same time, PE 2 and PE 3 respectively initiate a similar flood-prune process. Finally, three
independent SPTs are established in the MD. In the PIM-DM network, these independent SPTs constitute a
share-MDT.
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