[157811] in North American Network Operators' Group
Re: Whats so difficult about ISSU
daemon@ATHENA.MIT.EDU (Pete Lumbis)
Fri Nov 9 08:03:11 2012
In-Reply-To: <20121109073621.GA29358@pob.ytti.fi>
Date: Fri, 9 Nov 2012 08:02:49 -0500
From: Pete Lumbis <alumbis@gmail.com>
To: Saku Ytti <saku@ytti.fi>
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
I can't speak for JunOS, but none of the "new" IOS operating systems
are run to completion. This includes IOS-XE, XR and NX-OS.
On Fri, Nov 9, 2012 at 2:36 AM, Saku Ytti <saku@ytti.fi> wrote:
> When we start on that premise, we can do silly things like write
> run-to-completion operating systems like IOS and JunOS (rpd). Which means
> single guy making one bad judgement call, and whole OS is bad.
>
> Of course run-to-completion is most optimum way to execute code, if your
> code is flawless, but that ship has sailed. Possibly when IOS started CPU
> time was premium and it was cheaper to through code review money at the
> problem.
> But today it clearly is cheaper to add power to control plane and have
> levels of abstraction in control-plane which saves the system from bad
> code, i.e. design your control-plane assuming code you deliver isn't good.
>
