On Tue, Mar 14, 2017 at 2:42 PM, Stephen Hemminger <step...@networkplumber.org> wrote: > On Tue, 14 Mar 2017 14:10:22 -0700 > Roopa Prabhu <ro...@cumulusnetworks.com> wrote: > >> On Tue, Mar 14, 2017 at 1:25 PM, Stephen Hemminger >> <step...@networkplumber.org> wrote: >> > On Tue, 14 Mar 2017 11:48:37 -0700 (PDT) >> > David Miller <da...@davemloft.net> wrote: >> > >> >> From: Nikolay Aleksandrov <niko...@cumulusnetworks.com>
[snip] >> >> > 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. >> >> Stephen, is there any reason to have a per ecmp route multipath algo >> selection ?. >> All platforms have a global multipath selection algo. I also don't see >> routing daemons ready or willing to specify a per ecmp route multipath >> selection algo attribute. > > There is no compelling reason to make the attribute per route. But the > issue is more that configuration through sysctl's is problematic. It doesn't > fit into the standard API paradigm. Sysctl's are like routing patches not > part of the real CLI. Trying to trap sysctl's for things like switchedev > offload is particularly problematic. I can see the case for either way, > and don't have a fixed opinion. ok. understand the switchdev offload part. It was that way in the past...but today you can listen to sysctl updates on the netconf netlink channel. it works pretty well. > > The bigger discussion is trying to keep a record of the rationale for > decisions > such that there isn't buried tribal knowledge. This is why Dave has always > been > quite insistent on having discussions on the mailing list. There doesn't seem > to > be a good long term record other than Documentation/networking or commit logs. > agree. Most of the discussion around this has happened on the netdev mailing list so far. The previous set that updated ecmp algo tried to add a per route attribute and after review on this list was moved to on by default. Nikolay's first version included a per route attribute...to follow the previous ecmp work. Before Nikolay posted the second version, my feedback was to make it global. And this feedback was only re-iterated at last netconf/netdev. so, we can continue the discussion here if there are other opinions.
