From: Darby Weaver (darbyweaver@yahoo.com)
Date: Sun May 13 2007 - 01:17:37 ART
Kinda easy really...
Get to know your bit boundaries as Workerbee says...
But after you understand that...
Think like this:
Odds and Evens
142.102.5.0 0.0.8.255
142.102.10.0 0.0.4.255
What is 5+8 = Hint 13
What is 10+4 = Hint 14
See the easy way?
Same kind of math:
25+172 =197
142.102.25.0 and 142.102.197.0 ???
142.102.25.0 0.0.172.255
--- WorkerBee <ciscobee@gmail.com> wrote:
> I can do it with 2 lines:
>
>
> 142.102.5.0
> 142.102.10.0
> 142.102.13.0
> 142.102.14.0
>
> 3rd Octet
> -------------
> 00000101
> 00001101
> =======
> 00001000 > 142.102.5.0 0.0.8.255
> =======
>
> 3rd Octet
> -------------
> 00001010
> 00001110
> =======
> 00000100 > 142.102.10.0 0.0.4.255
> =======
>
> access-list 10 permit 142.102.5.0 0.0.8.255
> access-list 10 permit 142.102.10.0 0.0.4.255
>
> router rip
> version 2
> network 10.0.0.0
> distribute-list 10 in F0/0
> no auto-summary
>
> R3#show access-list 10
> Standard IP access list 10
> 10 permit 142.102.5.0, wildcard bits 0.0.8.255
> (14 matches)
> 20 permit 142.102.10.0, wildcard bits 0.0.4.255
> (14 matches)
>
> R3#show ip route rip
> 142.102.0.0/24 is subnetted, 4 subnets
> R 142.102.10.0 [120/1] via 10.10.10.1,
> 00:00:07, FastEthernet0/0
> R 142.102.13.0 [120/1] via 10.10.10.1,
> 00:00:07, FastEthernet0/0
> R 142.102.14.0 [120/1] via 10.10.10.1,
> 00:00:07, FastEthernet0/0
> R 142.102.5.0 [120/1] via 10.10.10.1,
> 00:00:07, FastEthernet0/0
>
> HTH
>
>
>
> On 5/13/07, Rob McDonald <robmexpert@gmail.com>
> wrote:
> > Guys,
> >
> > I am trying to do some filtering for the following
> routes coming from a BB.
> > The following are the routes that are being
> advertised by the BB.
> >
> >
> > 142.102.1.0
> > 142.102.2.0
> > 142.102.5.0
> > 142.102.6.0
> > 142.102.9.0
> > 142.102.10.0
> > 142.102.13.0
> > 142.102.14.0
> > 142.102.15.0
> >
> >
> >
> >
> >
> > Out of these I want to filter out the following:
> >
> >
> >
> > 142.102.5.0
> > 142.102.10.0
> > 142.102.13.0
> >
> > 142.102.14.0
> >
> >
> >
> > I have tried several ways to do it using an ip
> access-list but always still
> > the filtering doesn't work.
> >
> >
> >
> > ip access-list standard ROUTES
> > permit 142.102.5.0 0.0.15.0
> >
> > Is it possible to do this in 1 or 2 lines..... or
> no option other than doing
> > it in 4 lines?
> >
> >
> >
> > Thanks,
> >
> > --Rob
> >
> >
>
This archive was generated by hypermail 2.1.4 : Fri Jun 01 2007 - 06:55:20 ART