Errata >So your BGP route will not be inactive because of the unreachable next-hop.
So your BGP route *will be* inactive because of the unreachable next-hop. On Sun, Jul 22, 2018 at 11:52 PM, Pavel Lunin <[email protected]> wrote: > > > On Sun, Jul 22, 2018 at 9:45 PM, Andrey Kostin <[email protected]> wrote: > >> Hi Pavel, >> >> Thanks for replying. I understand how it works as soon as proper next-hop >> is present in a route. My attention was attracted by implicit next-hop >> conversion from pure IPv4 address to IPv4-mapped IPv6 next-hop from >> "Nexthop: YYY.YYY.155.141" in the advertised route to "Protocol next hop: >> ::ffff:YYY.YYY.155.141" in the received route. >> > > This is normal. In order to announce AFI/SAFI 2/1 update, you must have an > IPv6 next-hop. This is why it gets automatically converted. If you enable > BGP-LU, nothing will change in this terms, your next-hop address will still > be an IPv4-mapped IPv6 address. It will just be labeled. > > Same thing happens when you perform next-hop-self (or it's eBGP) for an > IPv6 route, announced via an MP-BGP session over IPv4. > > And ipv6-tunneling under mpls stanza is what makes your LDP/RSVP routes be > leaked from inet.3 to inet6.3 with automatic v4-to-v6 mapping. It's a > syntactic sugar, you can do the same with policies, explicitly leaking > inet.3 to inet6.3. > > I'm also wondering what could happen is there are no LSP available, which >> is rather unreal situation because everything will be broken anyway in this >> case. >> > If no LSP/FEC is available for the v4-mapped IPv6 next-hop, you won't have > an LDP/RSVP route in inet.3, thus it won't be leaked to inet6.3. So your > BGP route will not be inactive because of the unreachable next-hop. And > not, it's not so unusual. You can easily have your IGP up and running, but > someone forgot to add MPLS on one of the core interfaces. So your BGP > session and routes are up, IGP works but there is no labeled next-hop in > inet.3. > > -- > Pavel > _______________________________________________ juniper-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/juniper-nsp
