USB Devices
/private/var/log/system.log
To find USB Devices that have been connected to the computer you can search in System.log. You will be able to find the original first connection time, which is displayed along with the original “non-unique” USBMSC Identifier shown below in green. If you look at subsequent passages you will see the name of the device listed after “/Volume”, as shown below my device was named My Passport. Also if this is the first time that the device was connected you see the Universally Unique Identifier (UUID) which can be used for identification in later connections.
To access this log and reveal information about previously or currently connected USB Devices, copy and paste the following into the terminal.
open /private/var/log/system.log
Use the Command + F function to search for “USBMSC” to find each occurrence.