On 1/30/17 2:16 PM, Stephen Hemminger wrote: > My fear is that routing daemons already adapt to the funny semantics of > multi-path routing in IPv4 vs IPv6 > and therefore any change in semantics or flags risks breaking existing user > space.
That is a possibility, but so far the 2 open source code bases I know of have problems with IPv6 mpath. As I mentioned quagga does not work with IPv6 multipath as is today. I just looked at bird. IPv6 mpath support was added in Sept. 2016. It specifically hard codes not accepting RTA_MULTIPATH for IPv6 which I think is an odd choice and clearly coding to quirks as opposed to rtnetlink design. Having never looked at bird code I was able to get it working in < 1 hour. I will contact the patch author about that limitation. That said, the bird implementation needs work when you look at the add/delete/replace/append permutations, so the current code has its problems as well.
