> Supermicro motherboards also commonly default to having a feature that bonds the BMC network interface to one of the main NICs if you don’t plug a cable into the BMC interface. It’s common for people to be surprised that their BMC is exposed on their main network because they didn’t plug in a cable on the BMC NIC port at all.
Even if you changed the default from "failover" in the firmware you're just one CMOS reset (for whatever reason) away from it reverting back to putting the BMC on whatever network interface. This should really be something you can jumper off.