Duplicate MAC Addresses
Applies to: Medulla – Server
Version: All versions
Environment: On-Premise
Category: Medulla Agent / Inventory / MAC Duplicates
Why do some machines report to the wrong entity or create duplicates in GLPI?
In some environments, security or networking solutions (e.g., Fortinet) may create virtual network interfaces or mask the actual MAC addresses of machines.
In some cases, these solutions assign the same MAC address to multiple workstations.
This can cause abnormal behavior in Medulla, including:
- Devices registered in the wrong entity
- Inventory data reported to the wrong workstation
- Creation of duplicates or UUID conflicts in GLPI
- Unintentional merging of information across multiple machines
Important:
The MAC address is used as an identification key by the Medulla inventory engine. If multiple workstations have the same MAC address, the tool may consider them to be the same machine.
How can this problem be fixed?
You can blacklist problematic MAC addresses so they are no longer used when identifying workstations.
1. Edit the configuration file
Edit the following file:
/etc/pulse-xmpp-agent-substitute/registeryagent.ini.local2. Add the MAC address blacklist section
Add the following section, strictly adhering to case sensitivity and formatting:
[parameters]
blacklisted_mac_addresses = 00\:00\:00\:00\:00\:00, 00\:09\:0f\:aa\:00\:01, 00\:09\:0f\:fe\:00\:01, 20\:41\:53\:59\:4e\:ffYou must add the identical or problematic MAC addresses to be excluded to this configuration.
Important points:
- The address 00\:00\:00\:00\:00\:00 must be included.
- The character : must be escaped with \:.
- MAC addresses must be separated by commas.
3. Restart the assessment proxies
Once the change has been made, restart the substitutes:
restart-pulse-services allsubsRecommended step after making changes
After adding the MAC addresses to the blacklist and restarting the proxies, it is strongly recommended that you force the Medulla agents to reconfigure so that the workstations retrieve their new configuration, re-register correctly, and return a clean inventory.
Then follow the instructions in the following FAQ: