[Infrastructures] using IA methodologies to build network element configuration

[Brent Chapman]

At 10:59 AM -0500 3/30/05, Daniel Hagerty wrote:
>  > *cough* JunOS *cough*
>  >
>  > http://lists.freebsd.org/pipermail/freebsd-www/2005-January/002049.html
>
>     So can I schedule my emacs on my juniper as a real time process so
>that I'm always sure the only thing stopping me from typing is my
>garbage collection?  If I tell the juniper that my emacs is Really
>Important, can I starve Actually Important requests coming up from the
>hardware (e.g. process this bgp update RIGHT NOW because routing isn't
>consistent)?
>
>     Short of me being able to do that, I suspect a minor degree of
>embellishment.  I'm well aware that there's a real freebsd box in a
>juniper, but is this same freebsd box *really* the management
>processor for the routing hardware, or is it something attached to the
>side of the management processor?

The freebsd box is the management processor for the routing hardware, 
but it's not involved in most (if any) routing decisions.  The BSD 
system essentially loads firmware into all the custom chips on the 
interface cards that actually handle the packet, compiles the config 
into data that's also downloaded into the custom chips, and then gets 
the hell out of the way.  I'm not certain, but I believe it's 
possible for the management processor to crash but the routing engine 
and interface cards to keep running, at least until you want to make 
a config change.

This is a sensible design, in my opinion.

>     I suppose I should see if I can get my hands on a loaner juniper,
>just to satisfy my curiosity on exactly what the slicing looks like.
>More mail to send...

They're pretty cool boxes.  Many of Junipers founders and senior 
engineers are ex-Cisco, and they took advantage of considerable 
experience and a clean sheet of paper to do things "right" when they 
designed the Juniper boxes.


-Brent
-- 
Brent Chapman <brent@greatcircle.com> -- Great Circle Associates, Inc.
Specializing in network infrastructure for Silicon Valley since 1989
For info about us and our services, please see http://www.greatcircle.com/
Network Automation blog: http://www.greatcircle.com/blog/network_automation