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Advent of code in SPL - 2025 day 3
Day 3 is here . Part 1 This one isn't too difficult. Given a series of digits such as 818181911112111, we need to pick two digits (conserving the order) to make the highest 2-digit number possible, so in this example 92. The first digit is obviously the most important, so we always want the highest one available, but we need to reserve at least one digit at the end of the bank for the second digit. So take the bank, remove the last digit, and find the highest digit: Now f

Gabriel Vasseur
1 day ago4 min read


Advent of code in SPL - 2025 day 2
(Edited to use mvrange) Day 2 of the 2025 advent of code challenges is here: https://adventofcode.com/2025/day/2 You won't be able to do it if you haven't done day 1 first . We can break down this challenge in several steps: given a range (e.g. 11-22), enumerate all the IDs within the range (e.g. 11,12,13,...,22) given a number, assess whether it's made of 2 repeated halves somehow do this for all the ranges all together to get the solution Step 1 For this challenge, we'll s

Gabriel Vasseur
Jan 196 min read


Advent of code in SPL - 2025 day 1
Advent of code is a series of Christmas-themed programming challenges that's been running for more than 10 years now. While SPL is not exactly a fully-fledged programming language, I had heard in the past of at least one person (thank you Paul Dean for the idea!) attempting to do the challenges in SPL and this year I thought I would give it a go. I know it's more than a month too late, but this is the first of a series of articles tackling 2025's challenges in SPL. We won't

Gabriel Vasseur
Jan 123 min read


Shrink your windows event logs license costs with ingest actions!
Windows events are a large part of the volume of logs ingested in a lot of splunk deployments. Wouldn't be cool if we could shrink them so they don't eat up so much precious precious license? In this post I'll walk through how I rebuilt Windows Event Logs (WELs) into a compact, Splunk-friendly format, cuting size by up to 60% without breaking field extractions. Key takeaways With a few targeted ingest actions and props/transforms tweaks, you can shrink Windows logs dramatical

Gabriel Vasseur
Oct 27, 202510 min read


ES8 findings, intermediate findings, etc confusion!
The key thing I did not appreciate when I wrote the previous version of this post is that the Risk data model is now fed from...

Gabriel Vasseur
Sep 5, 20256 min read


RBA: Aggregate user & system risks!
Since RBA is all about aggregating security events that are related to the same entity, Assets & Identities normalisation is crucial to...

Gabriel Vasseur
Jan 6, 202512 min read


Untable, xyseries, transpose clarified!
These 3 table-manipulating commands are occasionally very useful but they are also quite confusing. For years, I've relied on the...

Gabriel Vasseur
Dec 2, 20241 min read


RBA: a better way to dedup risk events
In this post we’re discussing an advanced way to dedup risk events in your risk alerts (RIRs) and at the same time have the RIR results...

Gabriel Vasseur
May 22, 20234 min read
Linux tips
This for the most part isn't splunk-specific, but if you do any amount of administration on the linux command line, you might find it...

Gabriel Vasseur
Apr 30, 20225 min read


Splunk workload optimisation
Assess your search workload with this simple dashboard. Here's a very quick dashboard to identify what uses your splunk platform...

Gabriel Vasseur
Apr 26, 20221 min read


Dashboarding Best Practices, Tips & Tricks
Splunk’s “simple XML” dashboards are reasonably simple and straightforward to create, yet they are incredibly versatile and powerful. You...

Gabriel Vasseur
Oct 19, 20219 min read


Audit your correlation searches against your own Best Practices automatically
I did a talk at Splunk .conf21 about how to maintain correlation searches: pdf / mp4 . One of the topics is Correlation Searches Best...

Gabriel Vasseur
Oct 19, 202111 min read


Test your correlation searches end-to-end with Morning Checks
I did a talk at Splunk .conf21 about how to maintain correlation searches: pdf / mp4 . One of the topics is morning checks. Basically you...

Gabriel Vasseur
Oct 19, 20211 min read


Add an in-splunk after-the-fact Peer Review system for your correlations
I did a talk at Splunk .conf21 about how to maintain correlation searches: pdf / mp4 . One of the topics is having a simple peer review...

Gabriel Vasseur
Oct 19, 20212 min read


Add a simple TODO management system for your correlations
I did a talk at Splunk .conf21 about how to maintain correlation searches: pdf / mp4 . One of the topics is having a simple task...

Gabriel Vasseur
Oct 19, 20211 min read


Easy yet powerful submit buttons in your simple XML dashboards
There are a number of issues with Splunk’s simple XML forms submit button: you can't have more than one you can't move it you can't hide...

Gabriel Vasseur
Oct 18, 20213 min read
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