fuzzy times

A macro to give a human readable time to each event, like “earlier today” or “last month”.

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predicting and detecting anomalous behavior

Splunk 5.0 brings some interesting new anomaly prediction commands to the table. While I haven’t had time to really drill into everything that’s available, I did enjoy playing with the new predict command (nota bene that it has an even smarter cousin, x11, which understands seasonal patterns). Give it an event stream and it will give you a “band of normalcy” tracking the 95th percentile ceiling and floor… along with predictions of what those values might expand to.

Of course, as soon as we have a band of normalcy we might start thinking about notifying people if there are any events where reality leaves that band…

sourcetype="iis" | timechart span=1m count(dest) as distinct_count | predict distinct_count | rename upper95(prediction(distinct_count))

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Workflow Action and Blocklists

Extending the blocklists in Enterprise Security with workflow actions

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Simple Correlation in Splunk

As I promised at .conf, I’m going to start posting a series on writing effective correlation searches, in the hopes that I will get better at doing so.

First, framework. Alberto Cairo’s The Functional Art has a good summation of DIKW (Data, Information, Knowledge, Wisdom) Hierarchies. In short, we’re going to structure our search in a way that lets us gather Data, structure Information, and return Knowledge. This is what I called the correlation three-step in my .conf talk on Technology Add-ons: Gather a pool of Data, structure or extract Information for testing, test to acquire Knowledge. Hopefully that will lead to Wisdom, but any gaps are left as an exercise for the reader.

In order to keep it…

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Cognitive Splunking

Hi! Like Rob Reed I get a little excited when things go meta, and I’ve been spending a lot of time being excited at Splunk. One of the things that makes Splunk such a powerful tool is the fact that you can change your meta-cognition filters around on the fly via the magic of late-binding schemas. Index now, understand later is a pretty awesome trick, because it enables Splunk users to continue learning and leverage new understanding instead of getting stuck in whatever was sensible at the time of indexing. Since I spend my days on security and compliance problems this is an obviously useful mechanism, but I’d like to take a little time to write about why it’s

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