Yesterday was Mother’s Day and we are very thankful for our mothers! Today, we are releasing Security Onion 2.4.150 which includes a new Pro feature called MoM (Manager of Managers).

 If you have multiple Security Onion deployments, you’ll want to check out this new feature as it will allow you to manage all of them from a single manager!

You can read more about Manager of Managers in the MoM section of the documentation:

Elasticsearch Deletion Changes


As we mentioned in a previous blog post, this release includes changes for the Elasticsearch deletion process:

https://blog.securityonion.net/2025/04/upcoming-change-to-elasticsearch-index.html

Elasticsearch indices are managed by both the so-elasticsearch-indices-delete utility and Index Lifecycle Management (ILM). so-elasticsearch-indices-delete is primarily designed for single-node deployments like EVAL and STANDALONE configurations. Running it on a multi-node deployment with one or more search nodes has the possibility of getting into a corner case state where more data is deleted than intended. Because of this, we will disable this script on multi-node deployments when you update to this 2.4.150 release.

You will need to ensure that ILM is configured properly to delete indices before disk usage reaches the Elasticsearch watermark setting. Otherwise, Elasticsearch may stop ingesting new data. For more information, please see:

https://docs.securityonion.net/en/2.4/elasticsearch.html#index-management


Release Notes

There are many more features and fixes included in this release! For a complete list of all changes, please see the Release Notes:

https://docs.securityonion.net/en/2.4/release-notes.html#changes

Known Issues

For a list of known issues, please see:

https://docs.securityonion.net/en/2.4/release-notes.html#known-issues

About Security Onion

Security Onion is a free and open platform built by defenders for defenders. It includes network visibility, host visibility, intrusion detection honeypots, log management, and case management. 

For network visibility, we offer signature based detection via Suricata, rich protocol metadata and file extraction using your choice of either Zeek or Suricata, full packet capture, and file analysis. For host visibility, we offer the Elastic Agent which provides data collection, live queries via osquery, and centralized management using Elastic Fleet. Intrusion detection honeypots based on OpenCanary can be added to your deployment for even more enterprise visibility. All of these logs flow into Elasticsearch and we’ve built our own user interfaces for alerts, dashboards, threat hunting, case management, and grid management. 

Security Onion has been downloaded over 2 million times and is being used by security teams around the world to monitor and defend their enterprises. Our easy-to-use Setup wizard allows you to build a distributed grid for your enterprise in minutes!

Documentation

You can find our online documentation here:

https://docs.securityonion.net/en/2.4/

Documentation is always a work in progress. If you find documentation that needs to be updated, please let us know as described in the Feedback section below.

New Installations

If this is your first time installing Security Onion 2.4, then we highly recommend starting with an IMPORT installation as shown at:

https://docs.securityonion.net/en/2.4/first-time-users.html

Once you’re comfortable with your IMPORT installation, then you can move on to more advanced installations as shown at:

https://docs.securityonion.net/en/2.4/architecture.html

Existing 2.4 Installations

If you have an existing Security Onion 2.4 installation, you can update to the latest version using soup:

https://docs.securityonion.net/en/2.4/soup.html

Before updating your production deployment, we highly recommend testing the upgrade process on a test deployment that closely matches your production deployment if possible. This is especially important for releases that update components like Salt and Elastic.

2.3 EOL

As a reminder, Security Onion 2.3 reached End Of Life (EOL) on April 6, 2024:

https://blog.securityonion.net/2023/10/6-month-eol-notice-for-security-onion-23.html

Thanks

Lots of love went into this release!

Special thanks to all our folks working so hard to make this release happen!

  • Josh Brower
  • Jason Ertel
  • Corey Ogburn
  • Josh Patterson
  • Mike Reeves
  • Jorge Reyes

Questions, Problems, and Feedback

If you have any questions or problems relating to Security Onion 2.4, please use the 2.4 category at our Discussions site:

https://github.com/Security-Onion-Solutions/securityonion/discussions/categories/2-4

Security Onion Pro

We recently celebrated 10 years in business by announcing Security Onion Pro:

https://blog.securityonion.net/2024/07/celebrating-10-years-of-security-onion.html

Security Onion Pro includes many enterprise features that folks have been asking for:

  • Active Query Management
  • External API
  • Open ID Connect (OIDC)
  • Data at Rest Encryption
  • FIPS for the OS
  • DoD STIG for the OS
  • External Notifications in SOC
  • Time Tracking inside of Cases
  • Guaranteed Message Delivery
  • Manager of Managers

You can read more about these enterprise features at:

https://securityonion.com/pro

Training

Need training? Start with our free Security Onion Essentials training and then take a look at some of our other official Security Onion training!

https://securityonion.net/training

Security Onion Solutions Hardware Appliances

We know Security Onion’s hardware needs, and our appliances are the perfect match for the platform. Leave the hardware research, testing, and support to us, so you can focus on what’s important for your organization. Not only will you have confidence that your Security Onion deployment is running on the best-suited hardware, you will also be supporting future development and maintenance of the Security Onion project!

https://securityonion.com/hardware

Cloud Installations

For new Security Onion 2 installations in the cloud, this new version will soon be available on the AWS, Azure, and GCP marketplaces!

AWS Marketplace and Documentation:

https://securityonion.net/aws/?ref=_ptnr_soc_blog_250512

https://docs.securityonion.net/en/2.4/cloud-amazon.html

Azure Marketplace and documentation:

https://securityonion.net/azure

https://docs.securityonion.net/en/2.4/cloud-azure.html

GCP Marketplace and documentation:

https://securityonion.net/google

https://docs.securityonion.net/en/2.4/cloud-google.html

Screenshot Tour

If you want the quickest and easiest way to try out Security Onion 2.4, just follow the screenshots below to install an Import node. This can be done in a minimal VM with only 4GB RAM! For more information, please see:

https://docs.securityonion.net/en/2.4/first-time-users.html