[j-nsp] MX204 OSPF default route injection

[Saku Ytti]

On Thu, 7 Mar 2024 at 03:08, Lee Starnes via juniper-nsp
<juniper-nsp at puck.nether.net> wrote:

> Any tips or help on the best practice implementation would be greatly
> appreciated.

While what you want obviously is possible to accomplish. Is it a thing
you actually need? I don't personally really see any need to ever
carry default-route in dynamic routing protocols, in static protocols
there are use cases obviously.

Why not have a static floating default pointing to a dynamic recursive
next-hop at the CE? This solves quite a bit of problems in a rather
elegant way. One example being, if you generate a static route at
edge, you have no idea about the quality of the route, the edge device
may be entirely isolated and just blackholing all traffic. Whereas,
perhaps your candidate route is originated only from backbone devices
anycast loopback, and edge device is simply passing that host-route
towards CEs, this way the CE will recurse its default route to
whichever edge device happens to be connected and is passing the
default route along.

There are other examples of problems this addresses, discussed in this
and other lists in previous years.

-- 
  ++ytti