> On Mar 23, 2023, at 3:06 PM, Reshad Rahman <[email protected]> wrote: > >> In practice, what's often seen is that even with full coverage of the paths >> that there are end-to-end forwarding faults for various reasons. In at >> least some of these cases it's because BFD is implemented in a layer that >> isn't exercising the full data path. To pick a somewhat vendor neutral >> example, consider BFD implemented directly on the line card but not >> participating in the layer 3 ECMP load balancer, or at the LAG level not >> participating in the layer 2 equivalent. > <RR> That does seem to be a [in]correct implementation, but besides the > point...
Indeed, and a sore point. As someone who normally prefers to work in control-plane stuff, one of my favorite ways to get linecard engineers to turn interesting colors is to ask them "what payload can I use to deterministically exercise a given ECMP forwarding path for this card, for this set of software, for these chips revisions". -- Jeff
