Re: Snort doesn't react on rules - help a new snort user

[Heine Lysemose <lysemose () gmail com>]

Hi

You need to  decide whether you want to run Snort as IDS or IPS. IDS is
pure information gathering and with IPS you can make the Snort engine block
traffic/packets. You shouldn't provide the monitoring interface with an IP.

IDS
You need to set your monitor interface to promiscuous mode and the port it
is connected to on the switch needs to be set to span/mirroring.
If you're going this way I can really recommend NIDS distro called
SecurityOnion, http://securityonion.blogspot.com*.*

IPS
You need 3 interfaces, one for management and two for the bridge which
Snort will create for you. Your interfaces needs to be set to promiscuous
mode too.

To the command you need to add -Q (run in inline mode) and -i eth1:eth2
(adds the interface pair on which Snort creates the bridge)

I hope this will get you going,
Lysemose
On Apr 21, 2012 12:47 PM, "Simon Blixt" <blixten_496 () hotmail com> wrote:

>  Hi,
>
> I am new to Snort and just managed to set up v. 2.9.2 on Ubuntu 10.04. I
> have now created an own simple rule, just to try out my setup. It looks
> like this:
> alert tcp any any -> any any (content:"www.uid11.local""; msg:"First rule
> test"; sid: 132321;)
>
> And I run snort like this:
> /usr/local/lib/snort/bin/snort -u snort -g snort -c
> /usr/local/lib/snort/etc/snort.conf -i eth1
>
> But it doesn't work! Nothing happens. After I've hit CTRL+C I see that it
> has controlled xxx packets, but nothing more, no drops, alerts etc.
>
> My server running Snort got two interfaces, eth0 and eth1. eth0 got IP
> 10.10.10.3 and eth1 got 192.168.1.1.
>
> I got a webserver on the network 10.10.10.0-net with IP 10.10.10.1. And I
> have a client on 192.168.1.0-net with IP 192.168.1.10.
> To make it possible for my client to reach the webserver I've activated
> IPv4-forwarding in /etc/sysctl.conf on the server running Snort.
> So the client got 192.168.1.1 as it's default gateway, and the webserver
> 10.10.10.3.
>
> So my topology looks like this:
> [webserver]--------[IPS/Snort]-------------------[client]
> 10.10.10.1      10.10.10.3   192.168.1.1           192.168.1.10
>
> What else do you need to know? I need your help to figure out what my
> noobish head don't understand.
>
> Thank you in advance!
>
>
> ------------------------------------------------------------------------------
> For Developers, A Lot Can Happen In A Second.
> Boundary is the first to Know...and Tell You.
> Monitor Your Applications in Ultra-Fine Resolution. Try it FREE!
> http://p.sf.net/sfu/Boundary-d2dvs2
> _______________________________________________
> Snort-users mailing list
> Snort-users () lists sourceforge net
> Go to this URL to change user options or unsubscribe:
> https://lists.sourceforge.net/lists/listinfo/snort-users
> Snort-users list archive:
> http://www.geocrawler.com/redir-sf.php3?list=snort-users
>
> Please visit http://blog.snort.org to stay current on all the latest
> Snort news!
------------------------------------------------------------------------------
For Developers, A Lot Can Happen In A Second.
Boundary is the first to Know...and Tell You.
Monitor Your Applications in Ultra-Fine Resolution. Try it FREE!
http://p.sf.net/sfu/Boundary-d2dvs2

_______________________________________________
Snort-users mailing list
Snort-users () lists sourceforge net
Go to this URL to change user options or unsubscribe:
https://lists.sourceforge.net/lists/listinfo/snort-users
Snort-users list archive:
http://www.geocrawler.com/redir-sf.php3?list=snort-users

Please visit http://blog.snort.org to stay current on all the latest Snort news!