High throughput bgp links using gentoo + stipped kernel

Sun May 19 21:31:59 UTC 2013

On Sun, May 19, 2013 at 11:48:17AM -0400, Nick Khamis wrote:
> We do use a statefull iptables on our router, some forward rules...
> This is known to be on of our issues, not sure if having a separate
> iptables box would be the best and only solution for this?

I don't know about "only", but it'd have to come close to "best".  iptables
(and stateful firewalling in general) is a pretty significant CPU and memory
sink.  Definitely get rid of any stateful rules, preferably *all* the rules,
and apply them at a separate location.  We've always had BGP routing
separated from firewalling, but we're currently migrating from
one-giant-core-firewall to lots-of-little-firewalls because our firewalls
are starting to cry a little.  Nice thing is that horizontally scaling
firewalls is easy -- just whack 'em on each subnet instead of running
everything together.  Core routing is a little harder to scale out
(although as has been described already, by no means impossible).  The
important thing is to remove *anything* from your core routing boxes that
doesn't *absolutely* have to be there -- and stateful firewall rules are
*extremely* high on that list.

- Matt

-- 
When the revolution comes, they won't be able to FIND the wall.
		-- Brian Kantor, in the Monastery