Brocade VDX NOS 2.0.x and NOS 2.1.x admin guide and cli ref says this is the command to update the NOS firmware on VDX: firmware download usb directory firmware/nos2.1.0 It's not. Drop the 'firmware/' in the path. Correct and working (from 2.0.0 to 2.1.0 at least) is: firmware download usb directory nos2.1.0 I believe you need to have a Brocade USB. Perhaps it works with other sticks with the same folder layout, I don't know. And by the way, there are no release.plist file in the root of the nos2.1.0 folder. Brocade USB folder layout - one folder 'brocade' in the root and four subfolders: brocade/ config firmware firmwarekey support Updated 20120809.