If you're running discovery AND you haven't changed the default match rule for match_serial AND you're discovering devices using SSH, you may receive false positive matching when using OA 2.2.6. The bug is from a missing 2>/dev/null when retrieving the (newly introduced) Ubiquiti serial.
The details and patch are on the wiki errata page - [url]https://community.opmantek.com/display/OA/Errata+-+2.2.6+Serial+false+positive+matching[/url]
Apologies for any inconvenience caused
Mark.