Server side tracking: same Browser/anonymized IP ---> but different Visitor Ids, why?

I have activated:

  • Anonymize Tracking Data: 2 bytes (recommended)
  • Also use the Anonymized IP addresses when enriching visits: Yes

I have two computers with the exact same configuration (OS, browser, lang)

I am tracking server side, just giving IP, browser string and browser language, but I still get two visitors instead of expected one. IP anonymization (IP V6 used) works as expected.

$piwikTracker = new PiwikTracker($siteId, $matomoUrl);

I suspect IP anonymization happening AFTER fingerprint generation, although it says:

  • the IP address used to create the hash will be the anonimized IP address when you have enabled IP anonimisation which is the default privacy setting in Matomo (when you select “Also use anonymised IP when enriching visit: No” then the full IP address will be used in the hash calculation).