I know some people here have mentioned good experiences with ISSU on Nexus. I don't doubt that it usually works right, but in my latest experience with upgrading NX-OS on dual-SUP'ed 7k's, it was "hitless" if, by "hitless", you mean ~20% packet loss while troubleshooting with TAC before we found that we had to remove and re-apply QoS policies from every interface.
Also, depending on the update, linecards might have to be reset. Oliver ------------------------------------- Oliver Garraux Check out my blog: www.GetSimpliciti.com/blog Follow me on Twitter: twitter.com/olivergarraux On Thu, Nov 8, 2012 at 8:00 PM, Kasper Adel <karim.a...@gmail.com> wrote: > Does that mean they are the only vendor capable of doing this today? > > I am interested in the technology behind this if this is something public, > any ideas? > > Thx > > On Friday, November 9, 2012, Kenneth McRae wrote: > >> I have performed micro code upgrades using ISSU on the Juniper platform. >> >> On Thu, Nov 8, 2012 at 4:52 PM, Kasper Adel >> <karim.a...@gmail.com<javascript:_e({}, 'cvml', 'karim.a...@gmail.com');> >> > wrote: >> >>> What i was asking is full ISSU, even with micro code. I assume between >>> Major release there will be microcode upgrade most of the time. >>> >>> >>> On Fri, Nov 9, 2012 at 2:48 AM, Phil >>> <bedard.p...@gmail.com<javascript:_e({}, 'cvml', 'bedard.p...@gmail.com');>> >>> wrote: >>> >>> > The major vendors have figured it out for the most part by moving to >>> > stateful synchronization between control plane modules and implementing >>> > non-stop routing. >>> > >>> > ALU has supported ISSU on minor releases for many years and just added >>> > support for major releases. >>> > >>> > The Cisco Nexus ISSU works well, I've done an upgrade on a 5K switch and >>> > it was completely hitless. >>> > >>> > Juniper and Cisco with the 9K have gone through some hurdles but ISSU is >>> > actually usable now if the software versions support it. >>> > >>> > The main remaining hurdle is updating microcode on linecards, they still >>> > need to be rebooted after an upgrade. >>> > >>> > Phil >>> > >>> > On Nov 8, 2012, at 6:22 PM, Kasper Adel >>> > <karim.a...@gmail.com<javascript:_e({}, 'cvml', 'karim.a...@gmail.com');>> >>> wrote: >>> > >>> > > Hello, >>> > > >>> > > We've been hearing about ISSU for so many years and i didnt hear that >>> any >>> > > vendor was able to achieve it yet. >>> > > >>> > > What is the technical reason behind that? >>> > > >>> > > If i understand correctly, the way it will be done would be simply to >>> > have >>> > > extra ASICs/HW to be able to build dual circuits accessing the same >>> > memory, >>> > > and gracefully switch from one to another. Is that right? >>> > > >>> > > Thanks, >>> > > Kim >>> > >>> >> >>