i've got 6 machines advertising the same /32 at the moment, and bgp is typically quite stable in this setup.
sorry, i somehow misinterpreted (perhaps too hopefully) that the addition or removal of _flows_ would potentially cause a rehash, not just the addition or removal of a physical or logical path. back to the drawing board i go. On Sat, Aug 9, 2014 at 9:23 AM, Chris Woodfield <rek...@semihuman.com> wrote: > I've learned that the EX platform only allows 8 equal-cost routes. How > many proxies are in your setup? > > The behavior you're describing should only happen when one of the ECMP > routes is either withdrawn or a new route is advertised. > > Followup question: is the flow-hashing algorithm on the EX platform a > consistent hash (ring hash)? If so, only flows that were being mapped to > the withdrawn route, or that would be hashed to the new route, would be > affected. If it's not a consistent hash, then all flows would be re-mapped > to new routes whenever there's a change in the available next-hops. > > -C > > On Aug 9, 2014, at 9:00 AM, ryanL <ryan.lan...@gmail.com> wrote: > > oh man... this might be the answer to a long standing problem i've been > having with the EX4500's at my core. they do BGP to a bunch of proxy > machines (exabgp) that advertise the same /32 (as a VIP). once every so > often (becoming more often as traffic grows), a TCP packet is forwarded by > the EX to one of the machines which has no knowledge of the original flow. > that machine of course sends back a RST and breaks the whole flow. > > i've done exhaustive packet captures for juniper on this, thinking that > somehow the EX was actually duplicating a packet incorrectly out one > interface. but this stateless ECMP rehash for all flows every time a new > flow is added or taken away makes a lot more sense to me, and also really > sucks if true. > > case 2014-0123-0781, if anyone at juniper is listening. that case is > _still_ open. > > > _______________________________________________ juniper-nsp mailing list juniper-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/juniper-nsp