Hi Pavel,
Thanks for details. Looks like it's all documented except next-hop conversion... I guess that in "show route advertised-protocol" the address is shown before conversion because overwise it would be invalid and could not be announced... Kind regards, Andrey Pavel Lunin писал 22.07.2018 17:55: > 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 wrote: > >> On Sun, Jul 22, 2018 at 9:45 PM, Andrey Kostin 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 Links: ------ [1] mailto:ank...@podolsk.ru [2] mailto:plu...@gmail.com _______________________________________________ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp