Playing around with the idea of building a query for duplicate Mac address and so far "duplicate" is only offered on System Name. So perhaps a workaround would be to build a query that displays the Mac address and export out as a csv file. At that point you can filter for dup's...Just a thought..
Another idea is build this report:
- Click Menu, Reporting, Queries.
- Click New Query.
- Click System Management, Managed Systems and click Next.
- Select Single Group Summary Table for Display Results As.
- In the Labels Are: drop-down list, select MAC Address under Computer Properties , click Next, and then click Next again.
- Click Managed State under Managed Systems, select Equals from Comparison drop-down list, and select Managed from Value drop-down list.
- Click Run.
This will produce a report of MAC address by count. The majority should all be 1, and thus, not important to your troubleshooting. Anything 2 or greater you can click on the MAC and get a list of the computers, which you cna then export.