I did look into this a bit before. To be more specific:
IPv6 CEF appears to be functioning normally for prefixes longer than 64-bit on my 720(s). I'm not seeing evidence of unexpected punting. The CPU utilization of the software process that would handle IPv6 being punted to software, "IPv6 Input", is at a steady %0.00 average (with spikes up to 0.02%). So there would seem to be at least one major platform that is OK. On Wed, Dec 28, 2011 at 12:51 PM, Ryan Malayter <[email protected]> wrote: > > > On Dec 28, 9:44 am, Ray Soucy <[email protected]> wrote: >> For what its worth I haven't stress tested it or anything, but I >> haven't seen any evidence on any of our RSP/SUP 720 boxes that would >> have caused me to think that routing and forwarding isn't being done >> in hardware, and we make liberal use of prefixes longer than 64 >> (including 126 for every link network). They might just be under >> capacity to the point that I haven't noticed, though. I have no >> problem getting muti-gigabit IPv6 throughput. >> > > You can get >10GbE *throughput* from a Linux box doing all forwarding > in software as well. That's easy when the packets are big and the > routing tables are small, and the hash tables all fit in high-speed > processor cache. > > The general lack of deep information about how the switching and > routing hardware really works for IPv6 is my main problem. It's not > enough to make informed buying or design decisions. Unfortunately, I > have over the course of my career learned that a "trust but verify" > policy is required when managing vendors. Especially vendors that have > a near-monopoly market position. > > The problem, of course, is that verifying this sort of thing with > realistic worst-case benchmarks requires some very expensive equipment > and a lot of time, which is why the lack of solid information from > vendors and 3rd-party testing labs is worrying. > > Surely some engineers from the major switch/router vendors read the > NANOG list. Anybody care to chime in with "we forward all IPv6 prefix > lengths in hardware for these product families"? > -- Ray Soucy Epic Communications Specialist Phone: +1 (207) 561-3526 Networkmaine, a Unit of the University of Maine System http://www.networkmaine.net/
