On Tue, 14 Mar 2017 11:48:37 -0700 (PDT) David Miller <da...@davemloft.net> wrote:
> From: Nikolay Aleksandrov <niko...@cumulusnetworks.com> > Date: Tue, 14 Mar 2017 17:58:46 +0200 > > > On 14/03/17 17:55, Stephen Hemminger wrote: > >> On Tue, 14 Mar 2017 17:36:15 +0200 > >> Nikolay Aleksandrov <niko...@cumulusnetworks.com> wrote: > >> > >>> This patch adds support for ECMP hash policy choice via a new sysctl > >>> called fib_multipath_hash_policy and also adds support for L4 hashes. > >>> The current values for fib_multipath_hash_policy are: > >>> 0 - layer 3 (default) > >>> 1 - layer 4 > >>> If there's an skb hash already set and it matches the chosen policy then > >>> it > >>> will be used instead of being calculated (currently only for L4). > >>> In L3 mode we always calculate the hash due to the ICMP error special > >>> case, the flow dissector's field consistentification should handle the > >>> address order thus we can remove the address reversals. > >>> > >>> Signed-off-by: Nikolay Aleksandrov <niko...@cumulusnetworks.com> > >> > >> It is good to see ECMP come back from the grave. > >> Linux used to support it long ago but was abandoned after it was unstable > >> and removed from iproute2 in 2012. > >> > >> The old API was through route attributes which makes more sense than > >> doing it with sysctl. It makes more sense to use netlink instead. > >> Therefore please go back and do something like the old API rather than > >> doing it through > >> sysctl. > >> > > > > That's what my initial version did, but this was discussed during NetConf > > in Seville > > and it was decided that it's best to make a global sysctl, thus the change. > > > > Correct, we discussed this, and we all agreed to only have a sysctl for now. Why? If you are going to have private discussions please post the rationale in public.
