The document uses the IPv4 unicast AFI/SAFI where we need to have the same configuration for the VPNv4.
I have configured the following configuration on my BGP VPNv4 RR. However, the additional path (diverse path) is not advertise to the PE peer where is my case its IP address is 126.96.36.199. Following is the config of the VPNv4 RR:
Not straightforward reply on this one, as BGP PIC Edge (add-path) would only advertise paths that are, by definition, different.
Diverse-path is another kind of feature (which I have to admit I haven't seen it use in production anywhere, yet) usually used to perform something called Shadow Route Reflection (RR). A Shadow RR is simply a redundant RR that by using the diverse-path feature will advertise the secondary best path instead of the primary, allowing the topology to have diversity of paths overcoming the default behaviour of BGP of only advertising the best path.
This works even if the paths are considered same, that in VPNv4/v6 BGP, means same route distinguisher (RD) values. I assume you have the same RD received by your RR, since if the RDs are different for prefix x.x.x.x, separate best path selection will be run and BGP will select and advertise both anyways.
The mpath option will select the second best path in the multipath and avertise it accordingly.
Can you post the topology, as well as the following:
1. show bgp vpnv4 unicast all <PREFIX> - in the shadow RR.