On 19 Aug 2010, at 04:23, George Michaelson wrote:

>>> something which can take a couple of hundred basic and extended ACLs and 
>>> tell you
>>> these <ten> don't work
>>> these <twenty> conflict
>>> the remaining <x> have a sequence and can reduce to this basic <x-y> set
> A reasonable call. Its probably where we'll be by default, because there 
> isn't anything there and I think first principles upward is better than 
> paring back.
> [...]
> I think its clear a tool like I asked doesn't exist, and very probably won't, 
> anytime soon.

Hello

[ I'm sorry this reply is so late, holiday season ]

I understand the problem and think that it is partly caused by the complexity 
of keeping the acl configuration on all edge ports in sync, and keeping the acl 
definitions/purpose documented.

The way around this, is to have a configuration management system that records 
the detail of the ACL (description / ticket number - along with the filter 
specification in generic terms), which generates the configuration - or even 
better uses flow-specification to distribute the rules.  Further procedures to 
review the data in this management system periodically help this scale.

For the config management, this would tend to have to be locally bespoke (but 
simple to produce) in order to fit with existing policy and procedure, but the 
glue to push these rules out to routers is easy as open source tools exist :- 
  
http://labs.ripe.net/Members/thomas_mangin/content-exabgp-new-tool-interact-bgp 
  http://bgp.exa.org.uk/

Andy

Reply via email to