Heh you will find vendors avoid using the term hitless. I can't think of any
router which supports ISSU that is truly hitless. The ASR9K ISSU states it
will sustain less than 6 seconds of loss...
ISSU is still rife with caveats and incompatibilities as well if you are doing
more advanced things.
Phil
On Nov 8, 2012, at 8:22 PM, Oliver Garraux <oli...@g.garraux.net> wrote:
> 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
>
