* Iljitsch van Beijnum

> IPv6 BGP does in fact carry gloal and link local next hop addresses.

Yes, but my point is that if you don't configure a global (at least
non-link-local) prefix on the router interconnections, there's no global
address that can be announced as the BGP next-hop. With no global
address, the immediate link-local next-hop cannot be resolved in the
IGP, and the route is discarded. Or am I missing something?

For example, here's my BGP route to your e-mail domain. The key item
here is «Protocol next hop: 2a02:228:81:100::», which is the remote
router in the link-net to AS3292. If this link was numbered with
link-local addresses only, I don't see how this route could possibly be
used, unless you start mangling the BGP next-hop?

tore@cr2> show route 2001:1af8:2:5::2 active-path extensive    

inet6.0: 4377 destinations, 8940 routes (4376 active, 0 holddown, 1 hidden)
2001:1af8::/32 (3 entries, 1 announced)
TSI:
KRT in-kernel 2001:1af8::/32 -> {indirect(1048574)}
        *BGP    Preference: 170/-51
                Next hop type: Indirect
                Next-hop reference count: 5286
                Source: 2a02:c0:1000::2
                Next hop type: Router, Next hop index: 614
                Next hop: fe80::221:59ff:fe0e:9295 via xe-1/0/0.0, selected
                Protocol next hop: 2a02:228:81:100::
                Indirect next hop: 11355ac8 1048574
                State: <Active Int Ext>
                Local AS: 39029 Peer AS: 39029
                Age: 3:58:10    Metric: 20      Metric2: 2      MED-plus-IGP: 
22 
                Task: BGP_39029.2a02:c0:1000::2+179
                Announcement bits (2): 0-KRT 6-Resolve tree 4 
                AS path: 3292 16265 I
                AS path: Recorded
                Communities: 3292:1110 3292:24601
                Accepted
                Localpref: 50
                Router ID: 87.238.32.5
                Indirect next hops: 1
                        Protocol next hop: 2a02:228:81:100:: Metric: 2
                        Indirect next hop: 11355ac8 1048574
                        Indirect path forwarding next hops: 1
                                Next hop type: Router
                                Next hop: fe80::221:59ff:fe0e:9295 via 
xe-1/0/0.0
                        2a02:228:81:100::/127 Originating RIB: inet6.0
                          Metric: 2                       Node path count: 1
                          Forwarding nexthops: 1
                                Nexthop: fe80::221:59ff:fe0e:9295 via xe-1/0/0.0

-- 
Tore Anderson
Redpill Linpro AS - http://www.redpill-linpro.com/
Tel: +47 21 54 41 27
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