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Given a "ganged power switching" capable active USB2.0 hub, and - amongst other USB devices - an external HDD is attached to it. Most probably the electronics or the firmware of the external HDD has some issues, and every time it has its random glitch the system doesn't recognize the HDD anymore. I mean, lsusb doesn't list it anymore, however at least the disk is still spinning.

My question is that is there any software based way to make the HDD re-recognized, while the other devices in the HUB remain untouched? Some way that simulates as if I plugged the HDD right now into a particular port, replaying the needed handshake usually done when I plug in an USB harware (I assume there must be some protocol, but unfortunately I don't speak USB).

It implies that the following approaches are dead ends within the above context: * changing the USB hub to a per port power switching (HW based solution) * changing the HDD to a reliable one (HW based solution) * plug out and back into the HUB the HDD (HW based solution) * using usbreset or similar (will have impact on the other plugged in devices too, since I have a ganged power switching capable HUB) * playing with the USB related kernel modules (will have impact on the other plugged in devices too)

Worst case I can buy another HUB to put that between the original hub and the unreliable device(s) of course. But until that it is still an interesting question whether the above operation is possible at all.

Thank you in advance! cheers

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I can't think of a way that doesn't somehow involve restarting your USB stack, which would of course affect all your USB devices, not just the HDD.

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