Re: Certin ET rulesets and 100 percent usage.

["Randal T. Rioux" <randy () procyonlabs com>]

Forgive me if I'm wrong, but isn't using Snort to implement an IP
blocklist sub-optimal? Isn't this a better task for your firewall?

I just think an IDS should stick to what it does best.

Randy


On Thu, May 7, 2009 6:38 pm, Martin Roesch wrote:
> Yeah, you're hitting the rule chains iteratively and that's just not
> going to perform.  If you want to filter large sets of IP addresses that
> would be more properly implemented as a preprocessor with dedicated
> functionality.
>
> Marty
>
> On Thu, May 7, 2009 at 12:15 PM, Matt Jonkman <jonkman () jonkmans com>
> wrote:
> > Straight IP matching is something Snort doesn't do well. Unfortunately.
> >  So this isn't that unexpected.
> >
> > I'd only run those rulesets where you can afford the cycles. or run a
> > second snort for these alone and turn off everything in it's config to
> > streamline some.
> >
> > Matt
> >
> > jlay () slave-tothe-box net wrote:
> > > So here's something interesting.  Enabling ANY of the below rulesets
> > > results in snort using 100% CPU:
> > >
> > > emerging-botcc.rules emerging-compromised.rules emerging-drop.rules
> > > emerging-dshield.rules emerging-rbn.rules emerging-tor.rules
> > >
> > > Without snort uses around 49%.  Using 2.8.4.1 with about 700K average
> > >  traffic.  Any thoughts?  Thanks.
> > >
> > > James
> > >
> > >
> > >
> > >
> > > ---------------------------------------------------------------------
> > > --------- The NEW KODAK i700 Series Scanners deliver under ANY
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> > > the job done! With the NEW KODAK i700 Series Scanner you'll get full
> > > speed at 300 dpi even with all image processing features enabled.
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> > -- -------------------------------------------- Matthew Jonkman
> > Emerging Threats Phone 765-429-0398 Fax 312-264-0205
> > http://www.emergingthreats.net
> > --------------------------------------------
> >
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> >
> >
> >
> > -----------------------------------------------------------------------
> > ------- The NEW KODAK i700 Series Scanners deliver under ANY
> > circumstances! Your production scanning environment may not be a
> > perfect world - but thanks to Kodak, there's a perfect scanner to get
> > the job done! With the NEW KODAK i700 Series Scanner you'll get full
> > speed at 300 dpi even with all image processing features enabled.
> > http://p.sf.net/sfu/kodak-com
> > _______________________________________________ Snort-users mailing
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>
>
>
> -- Martin Roesch - Founder/CTO, Sourcefire Inc. - +1-410-290-1616
> Sourcefire - Security for the Real World - http://www.sourcefire.com
> Snort: Open Source IDP - http://www.snort.org
>
> -------------------------------------------------------------------------
> ----- The NEW KODAK i700 Series Scanners deliver under ANY circumstances!
> Your production scanning environment may not be a perfect world - but
> thanks to Kodak, there's a perfect scanner to get the job done! With the
> NEW KODAK i700 Series Scanner you'll get full speed at 300 dpi even with
> all image processing features enabled. http://p.sf.net/sfu/kodak-com
> _______________________________________________ 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
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------------------------------------------------------------------------------
The NEW KODAK i700 Series Scanners deliver under ANY circumstances! Your
production scanning environment may not be a perfect world - but thanks to
Kodak, there's a perfect scanner to get the job done! With the NEW KODAK i700
Series Scanner you'll get full speed at 300 dpi even with all image 
processing features enabled. http://p.sf.net/sfu/kodak-com
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