This Matomo plugin adds to your installation a new dimension called visit_subnetwork then reports visitor counts coming from private networks.
Settings are easily configurable by Matomo's General Settings administration page. You have two choices.
Private Address Space from RCF 1918, such as localhost 127.0.0.1, and IANA pre-defined networks 192.168.x.x, 172.16.x.x, 10.x.x.x.
Configure your custom subnet rule by writing a regular expression matching the IPv4 addresses of your other intanet mapped on the web (called extranet).
This plugin is a complete refactoring adapted and mantained for actual Matomo, of the first IntranetSubnetwork that was published for Piwik 2.x.
Just install by Matomo's Marketplace, or grab latest code from the Github repository.
This free software is licensed under GNU General Public License v3+
You can ask for support and your feedback is appreciated at plugin's issue center on Github.
Can I define my own intranet space?
Yes, you have a settings field inside General Administration page. You can choose pre defined IANA standard RCF Private Space and you can define your personal regular expression matching your custom network.
What is a regular expression?
Regex Are a sequence of characters that specifies a pattern.
How do I can test my regular expression rules?
There are useful tools online, such as Regex101
View and download this plugin for a specific Matomo version: