Re: per-FIB socket binding

On Sat, Dec 21, 2024 at 04:34:25PM +0000, Bjoern A. Zeeb wrote:
> On Tue, 17 Dec 2024, Mark Johnston wrote:
> 
> > Lately I've been working on adding FIB awareness to bind(2) and inpcb lookup.
> > Below I'll describe the project a bit.  Any feedback/comments/suggestions would
> > be appreciated.
> > 
> > Today, a TCP or UDP socket can receive connections or datagrams from any FIB.
> 
> SCTP?
> 
> > Any thoughts/comments?
> 
> How much use are FIBs still these days?  Half of the original use cases
> I can think of could easily and better be overcome by using vnet jails
> with a physical or virtual interface (e.g, vcc) being delegated to the
> vnet.
> 
> I wonder if anyone on FreeBSD is using FIBs to actually have multi-FIB
> forwardig but that very little touches your use case apart from the mgmt
> which again can be factored out better (or inversely, factoring out the
> forwarding).
nginx is aware of FIBs, and I use it to have one machine behind two
routers on same local net to present two different https sites, avoiding
virtual hosts.  Fib 0 and 1 are configured with different default routers.

Having to run whole vnet jail would mean much higher (admin) overhead
for this case without adding any useful functionality.

> 
> I would honestly know who and how FIBs are still in use today or if they
> should be put on a list to be removed for 16 (I assume I might be
> surprised).
> 
> 
> That all said with your opt-in approach if the code itself doesn't bring
> too many new complications I'd be happy with it (assuming FIBs still
> have a use case).
> 
> /bz
> 
> -- 
> Bjoern A. Zeeb                                                     r15:7