Try our new research platform with insights from 80,000+ expert users

Security Onion vs Splunk Enterprise Security comparison

 

Comparison Buyer's Guide

Executive SummaryUpdated on Jul 13, 2025

Review summaries and opinions

We asked business professionals to review the solutions they use. Here are some excerpts of what they said:
 

Categories and Ranking

Security Onion
Ranking in Log Management
22nd
Average Rating
7.6
Reviews Sentiment
5.5
Number of Reviews
3
Ranking in other categories
No ranking in other categories
Splunk Enterprise Security
Ranking in Log Management
2nd
Average Rating
8.4
Reviews Sentiment
7.4
Number of Reviews
327
Ranking in other categories
Security Information and Event Management (SIEM) (1st), IT Operations Analytics (1st)
 

Mindshare comparison

As of August 2025, in the Log Management category, the mindshare of Security Onion is 4.9%, up from 4.8% compared to the previous year. The mindshare of Splunk Enterprise Security is 7.4%, down from 9.6% compared to the previous year. It is calculated based on PeerSpot user engagement data.
Log Management
 

Featured Reviews

Jörg Kippe - PeerSpot reviewer
A mature and affordable solution that is easy to install and easy to update
The product takes time to learn, it's not that easy. In the beginning we had a lot of questions. If you want to use such a tool in an real (industrial) environment, you have to ask how to get the network data. Can we do a full packet capture? Can we provide agents to our end systems? There are no simple solutions to these questions. It's a general problem when running such systems in an industrial environment.
ROBERT-CHRISTIAN - PeerSpot reviewer
Has many predefined correlation rules and is brilliant for investigation and log analysis
It is very complicated to write your own correlation rules without the help of Splunk support. What Splunk could do better is to create an API to the standard SIEM tools, such as Microsoft Sentinel. The idea would be to make it less painful. In ELK Stack, Kibana is the query language with which you can search log files. I believe Splunk has also a query language in which they search their log files, but once you have identified the log file that you want to use for further security correlation, you want to very quickly transport that into your SIEM tool, such as Microsoft Sentinel. That is something that Splunk could make a little bit less painful because it is a lot of effort to find that log file and forward it. An API with Microsoft Sentinel or a similar SIEM tool would be a good idea.

Quotes from Members

We asked business professionals to review the solutions they use. Here are some excerpts of what they said:
 

Pros

"Security Onion is the most mature solution in the market."
"We use Security Onion for internal vulnerability assessment."
"The most valuable feature of Security Onion for security monitoring is its ability to find infected ports."
"It is a one stop shop as a full monitoring and alerting solution for operations and application analysis for most of our back-end systems."
"UBA, User Behavior Analytics, is a key feature."
"The most valuable function is the notable events. When I joined the team, I asked them what they could currently see, and they said nothing. I was pretty shocked. I know for a fact that they're using Enterprise Security or at least they had purchased it. I told them that there are several dashboards within Splunk that we can leverage. There is also notable events where we can see potential incidents or potential alerts about the infrastructure and the network itself."
"Capability to expand the functionality through custom code for data inputs, commands, visualization, alerts, and machine learning."
"It is easy to use in any environment."
"The most valuable feature is that it's very good for log aggregation."
"The initial setup is simple, not very complex. Initial deployment takes around 10 to 15 minutes to set up the entire base for Splunk including all three tiers."
"Splunk can extract all kinds of data. There's no limitation on what kind of structured and unstructured data one needs to extract — it can access any kind of data, including machine-generated data."
 

Cons

"Security Onion's user interface could be improved."
"The product is not easy to learn."
"The initial setup of the solution is a little bit difficult."
"The AWS add-on is particularly problematic, with most inputs requiring manual writing due to lack of out-of-box functionality."
"The access and identity features could be improved. For example, let's say we have onboarded 65 logs. Now, we can identify the various processes, but we run into trouble when we're updating the processes for AWS CloudTrail, EDR, MDR, and XDR."
"I do not have any pain points for Splunk Enterprise Security. I am still trying to learn it, but there can be more information on the education side for Splunk Enterprise Security. It would be nice if the certification path was more specific to what I use instead of being so broad."
"The GUI could be improved to include some of the capabilities that other BI solutions have. The layout is a little restrictive where you can’t resize all the panels to exactly how you would like them without tweaking some XML code."
"The main issue that I have with it is that the field transformations sometimes overlap with those in Splunk Enterprise, and then you get permissions issues that lead to troubles."
"Splunk can be an expensive solution. Technical support could be improved as well."
"I would like to get visibility into the data pipelines on heavy forwarders and indexers to see exactly their source and the cause of saturation when it occurs. This would help us learn even more about our high use applications."
"The area of concern revolves around the fact that Splunk is an expensive product."
 

Pricing and Cost Advice

"Security Onion is a free solution."
"It is an open-source solution."
"Security Onion is an open-source solution."
"From what I have seen so far, Splunk has multiple cost models. The one that we are using is pretty good when it comes to ingesting data into the environment. It has worked out pretty well."
"Our ROI is high."
"Splunk Enterprise Security incurs a significant cost because of the amount of data we send, but we are fine with the value we're getting for that price."
"The Splunk Enterprise Security license is expensive."
"I would highly recommend anyone evaluating this option to download the free trial which allows for the ingestion of 500MB of data per day in order to get a feel for what Splunk does at its core. It will get pricey once your ingestion rates start to sky rocket, but I would consider it expensive given the amount of information that it allows you to analyze and react on straight out-of-the-box."
"The pricing model is based on the number of gigabytes that you ingest into the Splunk system. So it can be an expensive solution."
"There is an annual license required to use this solution."
"We have an unlimited one, and we pay yearly, but I don't know how much it costs. Previously, I worked for a startup, and when they started building it up, it was complicated for them because they didn't have the budget for that many licenses. It was very costly for them. So, startups might find it a little bit problematic because of the licensing, but for bigger companies, there is no issue."
report
Use our free recommendation engine to learn which Log Management solutions are best for your needs.
865,295 professionals have used our research since 2012.
 

Comparison Review

VS
Feb 26, 2015
HP ArcSight vs. IBM QRadar vs. ​McAfee Nitro vs. Splunk vs. RSA Security vs. LogRhythm
We at Infosecnirvana.com have done several posts on SIEM. After the Dummies Guide on SIEM, we are following it up with a SIEM Product Comparison – 101 deck. So, here it is for your viewing pleasure. Let me know what you think by posting your comments below. The key products compared here are…
 

Top Industries

By visitors reading reviews
Computer Software Company
12%
University
11%
Comms Service Provider
10%
Government
10%
Computer Software Company
14%
Financial Services Firm
14%
Manufacturing Company
8%
Government
7%
 

Company Size

By reviewers
Large Enterprise
Midsize Enterprise
Small Business
No data available
 

Questions from the Community

What do you like most about Security Onion?
The most valuable feature of Security Onion for security monitoring is its ability to find infected ports.
What is your experience regarding pricing and costs for Security Onion?
Security Onion is an open-source solution. On a scale from one to ten, where ten is expensive and one is cheap, I rate the solution's pricing a six out of ten.
What needs improvement with Security Onion?
The initial setup of the solution is a little bit difficult.
What SOC product do you recommend?
For tools I’d recommend: -SIEM- LogRhythm -SOAR- Palo Alto XSOAR Doing commercial w/o both (or at least an XDR) is asking to miss details that are critical, and ending up a statistic. Also, rememb...
What is a better choice, Splunk or Azure Sentinel?
It would really depend on (1) which logs you need to ingest and (2) what are your use cases Splunk is easy for ingestion of anything, but the charge per GB/Day Indexed and it gets expensive as log ...
How does Splunk compare with Azure Monitor?
Splunk handles a high amount of data very well. We use Splunk to capture information and as an aggregator for monitoring information from different sources. Splunk is very good at alerting us if we...
 

Overview

 

Sample Customers

Information Not Available
Splunk has more than 7,000 customers spread across over 90 countries. These customers include Telenor, UniCredit, ideeli, McKenney's, Tesco, and SurveyMonkey.
Find out what your peers are saying about Security Onion vs. Splunk Enterprise Security and other solutions. Updated: July 2025.
865,295 professionals have used our research since 2012.