This solution applies to Yosemite Server Backup Version 8.8 and newer.
You can identify your media by opening the Yosemite Server Backup Administrator and selecting Devices on the left. On the right, expand down to the device or slot you wish to identify the media in. Right-click on this and select Identify from the right-click content menu. Once complete, the log will open in a new window. You can view this log later from under Status and Logs.
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