Snort mailing list archives

Re: Snort rules maximum rules per file


From: Martin Holste <mcholste () gmail com>
Date: Fri, 1 Jul 2011 13:56:48 -0500

You are using the wrong tool for URL blocking.  You should be using
squid for this with policy-based routing to transparently redirect all
requests through squid as a transparent proxy.

On Fri, Jul 1, 2011 at 1:12 PM, Hussein Bahaidarah <husseinb () gmail com> wrote:
Hello,
no warning was displayed.
All rules are simple and of the following format:
alert tcp any any -> any 80 ( content:"URL"; react:; sid:1; )
The content is changed on every rule which is basically a URL and the SID is
incremented from 1 to 942099
My system has 4GB memory. Before using snort 600MB is used and after snort
full memory is utilized. That is on 2.9.0.5. Now, I have switched to Version
2.9.1_beta as the "react" option was not firing on multiple rules.
I am testing snort with IXIA; but the result are not good as it seems that I
am not configuring Snort in the right way. I need to achieve blocking for a
big number of URL's with snort. Do you have any recommendations in this
regards to tweak and optimize snort performance.
Thanks,
On Jun 29, 2011, at 7:52 PM, Russ Combs wrote:
We have kicked this around internally, and don't have a simple configuration
suggestion to try so a few questions ...

Did you see any warnings in the startup output when you loaded 942099 rules?

What kind of rules are these?  Are they all very simple rules or rules with
lots of options?

How much memory does your system have?  How much is used before and after
starting Snort with all those rules?

Thanks
Russ

On Sun, Jun 26, 2011 at 1:04 PM, Hussein Bahaidarah <husseinb () gmail com>
wrote:

Hello,
I have found after extensive testing that only 131008 rules only fires
alert and action. Any rule after that will not take any action.
On Jun 25, 2011, at 8:39 PM, Hussein Bahaidarah wrote:
Hello,
Is there a limit on the number of rules support by snort in general? and
on per file basis? I have customized a file with 942099 rules and it took
about 15 minutes to start snort; but no alerts or actions wer fired.
+++++++++++++++++++++++++++++++++++++++++++++++++++
Initializing rule chains...
942099 Snort rules read
    942099 detection rules
    0 decoder rules
    0 preprocessor rules
942099 Option Chains linked into 1 Chain Headers
0 Dynamic rules
+++++++++++++++++++++++++++++++++++++++++++++++++++
+-------------------[Rule Port
Counts]---------------------------------------
|             tcp     udp    icmp      ip
|     src       0       0       0       0
|     dst  942099       0       0       0
|     any       0       0       0       0
|      nc       0       0       0       0
|     s+d       0       0       0       0

+----------------------------------------------------------------------------
--
Regards,
Hussein Bahaidara


------------------------------------------------------------------------------
All of the data generated in your IT infrastructure is seriously valuable.
Why? It contains a definitive record of application performance, security
threats, fraudulent activity, and more. Splunk takes this data and makes
sense of it. IT sense. And common sense.
http://p.sf.net/sfu/splunk-d2d-c2
_______________________________________________
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 see http://www.snort.org/docs for documentation



------------------------------------------------------------------------------
All of the data generated in your IT infrastructure is seriously valuable.
Why? It contains a definitive record of application performance, security
threats, fraudulent activity, and more. Splunk takes this data and makes
sense of it. IT sense. And common sense.
http://p.sf.net/sfu/splunk-d2d-c2
_______________________________________________
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 see http://www.snort.org/docs for documentation


------------------------------------------------------------------------------
All of the data generated in your IT infrastructure is seriously valuable.
Why? It contains a definitive record of application performance, security 
threats, fraudulent activity, and more. Splunk takes this data and makes 
sense of it. IT sense. And common sense.
http://p.sf.net/sfu/splunk-d2d-c2
_______________________________________________
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 see http://www.snort.org/docs for documentation


Current thread: