[Snort-users] Snort home net and external net question

waldo kitty wkitty42 at ...14940...
Fri Sep 3 12:48:25 EDT 2010


On 9/3/2010 11:01, Andy Berryman wrote:
> If I have my home net of snort set to:
>
> var HOME_NET [10.215.0.0/16]
>
> How can I make my external net be !$HOME_NET and 10.215.40.0/24 subnet?

if i'm reading that right, then your HOME_NET is incorrect if 10.215.40.0/24 is 
not part of it...

the following make up the 10.215.0.0/16 network without 10.215.40.0/24 in it... 
the numbers in parenthesis are the range of addresses in that CIDR...

10.215.0.0/19 (10.215.0.0 - 10.215.31.255)
10.215.32.0/21 (10.215.32.0 - 10.215.39.255)
10.215.41.0/24 (10.215.41.0 - 10.215.41.255)
10.215.42.0/23 (10.215.42.0 - 10.215.43.255)
10.215.44.0/22 (10.215.44.0 - 10.215.47.255)
10.215.48.0/20 (10.215.48.0 - 10.215.63.255)
10.215.64.0/18 (10.215.64.0 - 10.215.127.255)
10.215.128.0/17 (10.215.128.0 - 10.215.255.255)

so you would have your HOME_NET set like this...

var HOME_NET [10.215.0.0/19, 10.215.32.0/21, 10.215.41.0/24, 10.215.42.0/23, 
10.215.44.0/22, 10.215.48.0/20, 10.215.64.0/18, 10.215.128.0/17]

and then your external net would be !HOME_NET because 10.215.40.0/24 is already 
not listed as part of your home network ;)





More information about the Snort-users mailing list