North American Network Operators Group

Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical

Re: 10GE router resource

  • From: Adrian Chadd
  • Date: Thu Mar 27 02:29:08 2008

On Thu, Mar 27, 2008, Andrew C Burnette wrote:

> Indeed. PCI-X is already an EOL'ed interface, if only cheap PCI-X cards 
> were available. Once you add extensive ACL's, there's loads more 
> [central] processing to be done than just packet routing (100k choices 
> versus 2 to 4 interfaces). System throughput gets slammed rather 
> quickly. Linux IPtables grumbles painfully at 100k line ACLs :) Not to 
> mention the options of what to do with a packet are very limited.

I agree, and the rest of the discussion is interesting, but the iptables
deployments I've seen which do massive ACLs like this almost certainly end
up having ACLs you can collapse into a small number of set-lookup-and-act

Those set-lookup-and-act rules are much faster than the linear ACL lookups
which ipfw/iptables/ipf/pf/etc do by default (and all of them support
IP sets in some form or other); I did this trick recently to reduce the CPU
overhead on an old revision 2.8ghz P4 from 99% to <10% when routing 100mbit
of average-pps TCP.