Lansweeper uses the MAC address as the unique identifier for non-Windows assets. If the MAC address is not available, the IP address will be used instead. More information on this unique identifier can be found in the following knowledgebase article: https://www.lansweeper.com/knowledgebase/how-lansweeper-uniquely-identifies-assets/
When saving the scanned information in the database, Lansweeper will first check if this unique identifier already exists. If this is the case, the existing asset will be updated and if not, the new asset will be added. Do note that Lansweeper compares all MAC addresses for both assets (meaning also for linked components). If there's a match for any of them, the assets will merge and the newly scanned data will update the existing asset. When a merge occurs this should be visible in the Comments tab of the asset. We assume you've redacted your comment as the shared MAC address(es) should be listed in the comment as per the example below.
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As seen in the screenshot above, we very recently added an additional check on the serial number as well. It is worth noting that only the scanned serial numbers are compared, so a merge will only occur if the existing and scanned asset share the exact same serial number. If no serial numbers are detected or if a serial was only detected for one of the assets (existing or scanned), no merge will occur and the logic will revert to MAC-based merging which seems to be the case here. Important note: manually editing the serial in the web console, will not affect this new merge logic.
There is a workaround for these merges by adding the affected MAC address(es) to an internal list in the Lansweeper database (tsysMacBlacklist). Adding the common MAC Address(es) to tsysMacBlacklist will prevent Lansweeper from using the common MAC address(es) to uniquely identify assets and will allow both assets to be added to the database.
To blacklist a shared MAC address you can execute the below script. Replace the highlighted parts of the code with the MAC address that you would like to exclude and you can also give it a more meaningful exclusion name. To execute scripts you can make use of the DatabaseMaintenance tool, which can be found under Program Files (x86)\Lansweeper\Tools on your Lansweeper server. Note that as this is a database script, just to be safe, we suggest taking a back-up of your database as described in the following article: https://www.lansweeper.com/knowledgebase/backing-up-your-installation/
INSERT INTO tsysMacBlacklist (Mac, Comment) VALUES ('AA:BB:CC:00:11:22', 'Exclusion name')
GO
UPDATE tsysupdate SET MacBlacklist = GETDATE()