[157804] in North American Network Operators' Group
Re: Whats so difficult about ISSU
daemon@ATHENA.MIT.EDU (Mikael Abrahamsson)
Thu Nov 8 23:13:51 2012
Date: Fri, 9 Nov 2012 05:13:26 +0100 (CET)
From: Mikael Abrahamsson <swmike@swm.pp.se>
To: NANOG list <nanog@nanog.org>
In-Reply-To: <AB4074C9-7F5D-4529-8E0A-1D434B8E9D9F@gmail.com>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Thu, 8 Nov 2012, Phil 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.
NSR isn't ISSU.
ISSU contains the wording "in service". 6 seconds of outage isn't "in
service". 0.5 seconds of outage isn't "in service". I could accept a few
microseconds of outage as being "ISSU", but tenths of seconds isn't in
service.
> The main remaining hurdle is updating microcode on linecards, they still
> need to be rebooted after an upgrade.
... and as long as this is the case, there is no ISSU. There is only
"shorter outages during upgrade compared to a complete reboot".
--
Mikael Abrahamsson email: swmike@swm.pp.se
