Snort mailing list archives
Re: Packet Performance Monitor
From: Mike Cox <mike.cox52 () gmail com>
Date: Mon, 3 Oct 2016 15:01:08 -0400
Thanks Russ, much appreciated. This kind of begs the question, when PPM suspends a rule, does the single rule get suspended or the entire tree (which could be multiple rules)? Thanks. -Mike Cox On Mon, Sep 26, 2016 at 8:57 AM, Russ <rucombs () cisco com> wrote:
Hey Mike, This has been a "feature" of Snort for quite a while and likely will only be fixed in Snort++, which inherited the issue. It arose when we added a performance feature to compile all the rules that share a fast pattern match end state into a single tree that can be evaluated more quickly than iterating over the individual rules. Such rules tend to have a lot in common and the common part is evaluated just once. Consequently, when the tree triggers a latency event, it could be one or more rules that are at fault. I'm thinking we will add a mapping and report the index that can be used to find the rules. This is in our backlog. Thanks Russ On 9/26/16 8:27 AM, Mike Cox wrote: Perhaps snort-sigs was the wrong place to post this. Removing them and adding snort-devel. Thanks. Mike Cox On Thu, Sep 22, 2016 at 10:59 AM, Mike Cox <mike.cox52 () gmail com> wrote:I've been messing around with the Packet Performance Monitor (PPM) preprocessor and it seem like a nice capability of Snort. However, when I configure it to suspend/disable expensive rules once the thresholds are reached, how do I know which rule was suspended? I see it generates the GID 134 alert along with the packet it was considering at the time but I need to be able to know what rule was suspended so I can: 1) account for and correlate the coverage gap (if necessary) 2) tune the rule Thanks! Mike Cox------------------------------------------------------------------------------ _______________________________________________ Snort-devel mailing listSnort-devel@lists.sourceforge.nethttps://lists.sourceforge.net/lists/listinfo/snort-devel Archive:http://sourceforge.net/mailarchive/forum.php?forum_name=snort-devel Please visit http://blog.snort.org for the latest news about Snort!
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Current thread:
- Re: Packet Performance Monitor Mike Cox (Oct 03)
- Re: Packet Performance Monitor Russ (Oct 03)