Status of ECMP Support in 22.1

[GuardedAirplane]

I have seen several old posts indicating that the switch to FreeBSD 13 in 22.1 would bring ECMP support, but I don't see it listed in the GUI yet. Is this feature available now and just lives behind a tunable or will it be offered as a future point release or is it delayed to a future major release like 22.7 or later?

Thank you in advance for the update!

[GuardedAirplane]

Specifically I am looking for support of a "resilient ECMP" algorithm for use with BGP via MetalLB as seen in this documentation page:

https://metallb.universe.tf/concepts/bgp/

[mimugmail]

FRR supports all required features and you only need to set multipath in tunables, then its up to the community to test it

[GuardedAirplane]

So just to confirm would this look like the following:

Tunable: multipath
Description: Enables ECMP
Value: <up to X way ECMP>

I got this from the FFR documentation, but it seems like it is only a build flag not a runtime one.

Do you have any information about selecting a hashing algorithm as mentioned in the MetalLB docs or is that just inherent to ECMP? Apologies if that is a dumb question, I am still kinda a noob when it comes to advanced networking like this.

[franco]

name is "net.route.multipath" and value to enable is "1".

Note that the routing can fall apart when using multi-wan in this brave new world with multiple default routes we cannot cope with yet from the non-FRR side.


Cheers,
Franco

[GuardedAirplane]

Thanks Franco! I am just tinkering with now as a hobby, so multi-wan is not something I have to deal with at the moment.

Do you have any information about the hashing algorithm or is that likely not an issue?

[franco]

The hashing side was handled in this review https://reviews.freebsd.org/D26523

It looks to be RSS compatible (Toeplitz).

Of course things could have changed since this review was merged.


Cheers,
Franco