Re: [PATCH v2 3/3] Optimize route dependency solver.

[Martin Schitter <ms+git@mur.at>]

On 9/19/26 15:07, Stefano Brivio wrote:
> Just a quick comment before you risk losing a lot of time (I'm really
> not sure though): there*might* be interdependencies between routes in
> 1. and between routes in 2., especially with 'nexthop' objects. And
> IPv6 has several scopes. Maybe it all works thought, I haven't checked
> your iproute reference yet.

This alternative approach is looking for route table entries in exactly 
the same tables and scopes. There is no difference in this regard. It's 
just using a more rational strategy to minimize dependency errors.

The most common cause for EHOSTUNREACH and ENETUNREACH errors are 
related to attempts adding a route without having defined the local exit 
capabilities first. There are still a few other possible reasons causing 
these particular errors (policy routing, disabled interfaces, etc.), but 
those cases are also not solved by any of our previous solutions! The 
errors just got ignored after many useless loops and costly operations.

You can iterate as often as you like over this list of route entries and 
try to add them, but the amount of dependency errors will stay the same 
after just a few attempts (those, which define the elementary local host 
and network route connectivity information).

We don't have to solve a complex network of transitive dependency 
relations, but only respect the much simpler order of dependency 
relations between very few different classes of entries.

Well, that's at least my current understanding of this issue.
But I still have to further think about it and test it in practice...