IS-IS and IPv6 LLA next-hop - just Arista, or everyone?

Tue May 4 06:44:21 UTC 2021

On Tue, 4 May 2021 at 07:24, Mark Tinka <mark at tinka.africa> wrote:

> Junos:
>> 2c0f:feb0::1/128   *[IS-IS/18] 02:43:49, metric 5870
>                        to fe80::1205:caff:fe86:4ac3 via et-4/0/2.0
>                        to fe80::5287:89ff:fef3:25c3 via et-4/0/2.0
>                        to fe80::1205:caff:fe86:4b10 via et-5/0/2.0
>                     >  to fe80::5287:89ff:fef3:2610 via et-5/0/2.0
>
> IOS XE:
> I2  2C0F:FEB0::1/128 [115/6410]
>      via FE80::1205:CAFF:FE86:4AC3, TenGigabitEthernet1/0/0
>      via FE80::1205:CAFF:FE86:4B10, TenGigabitEthernet0/0/0
>      via FE80::5287:89FF:FEF3:25C3, TenGigabitEthernet1/0/0
>      via FE80::5287:89FF:FEF3:2610, TenGigabitEthernet0/0/0
>
> IOS XR:
> i L2 2c0f:feb0::1/128
>       [115/5870] via fe80::1205:caff:fe86:4b10, 02:45:22, HundredGigE0/3/0/0 (!)
>       [115/5810] via fe80::f60f:1bff:feb0:75c4, 02:45:22, HundredGigE0/2/0/1
>

SROS:
2001:218:0:1000::1/128                        Remote  ISIS      48d22h13m  18
       fe80::42de:adff:fe98:87e4-"lag1"                             25301

----
https://tools.ietf.org/html/rfc5308

For Hello PDUs, the "Interface Address" TLV MUST
   contain only the link-local IPv6 addresses assigned to the interface
   that is sending the Hello.  For LSPs, the "Interface Address" TLVs
   MUST contain only the non-link-local IPv6 addresses assigned to the
   IS.
----

These are hello derived:
A:ytti at a04.chcgil09.us.bb# show router isis adjacency
r22.chcgil09.us.bb-re0 detail |match Neigh
IPv6 Neighbor     : fe80::42de:adff:fe98:87e4
IPv4 Neighbor     : 129.250.3.205

Vendors do not have the option to use GUA while being RFC5308 compliant.

-- 
  ++ytti