Did you know Security Onion works on both Internet-connected and airgap networks? Our ISO image includes everything you need to run without Internet access. Make sure that you choose the Airgap option during Setup:
If your network has Internet access but has overly restrictive proxies, firewalls, or other network devices that might prevent Security Onion from connecting to certain Internet sites, then you may want to consider the Airgap option as everything will install from the ISO image itself.
For more information, please see the Airgap section of our documentation:
https://docs.securityonion.net/en/2.4/airgap.html
