Thanks Michael :-)

 

Your absolutely right, only 10 and 14

 

the 13 has been permitted with the 10.10.5.0 0.0.8.0 

 

But still confused a little, why 0.0.4.0?

 

10 - 0000 1010

14 - 0000 1110

 

 

 

Cheers!

Antonio

 

From: michael haynes [mailto:[email protected]] 
Sent: Monday, 18 May 2009 11:31 PM
To: Antonio Dee Hotmail
Cc: CCIE_RS OnlineStudyList
Subject: Re: [OSL | CCIE_RS] ACL filtering blues

 

If I'm thinking about your question correctly, you can't filter the way
you've described using only ONE access list.  If you use access-list 1
permit 10.10.10.0 0.0.4.0, I think you will get 10.10.10.0 and 10.10.14.0,
but not 10.10.13.0.  You would need another access list just for that
network.

 

Any else agree or disagree?

 

Michael

On Mon, May 18, 2009 at 9:53 AM, Antonio Dee Hotmail
<[email protected]> wrote:

Hi All,

 

Need some help on ACL calculation. This is general ACL filtering scenario.

 

I'm just practicing on ACL filtering especially on the non-continuous
wildcards.

 

i've injected this to my test router but i don't seem to get the logic why
it's this wildcard. can somebody enlighten me on this?

 

I know 0 in the wildcard are care bits and 1 don't care, just the opposite
of a subnet mask.

 

Example Scenario:

 

I get this networks from a backbone router:

 

network 10.10.10.0

network 10.10.11.0

network 10.10.12.0

network 10.10.13.0

network 10.10.14.0

network 10.10.15.0

network 10.10.16.0

 

I want to filter on the third octet and allow only 10, 13, 14 to come in

 

been playing with various values on the wildcard, and the working value is
0.0.4.0 , WHY????

 

 

Kind Regards,

Antonio

 

 

 

 

Reply via email to