>> Device is GOOD >> >> I also created a big file with dd using /dev/urandom with the same size >> as my flash drive, copied it once and read it three times. The SHA-1 >> checksum is always the same and matches the original one on the hard disk. >> >> So after much testing I feel I can conclude that my USB flash drive is >> not fake and it is not defective. >> > For what it's worth, there's multiple other things that could cause similar > issues. I've had a number of cases where bad USB hubs or poorly designed > (or just buggy or failing) USB controllers caused similar data corruption, > the most recent one being an issue with both a bad USB 2.0 hub (which did > not properly implement the USB standard, counterfeit USB devices come in all > types) and a malfunctioning USB 3.0 controller (which did not properly > account for things that didn't properly implement the standard and had no > recovery code to handle this in the drivers). I ended up in most cases > checking the ports using other USB devices (at least a keyboard, a mouse, > and a USB serial adapter).
Similar as Austin, I also want to note that there might be USB related issues that only pop-up after some time and not in tests. For example, this weekend I connected a 2.5inch 500G drive with its Y-cable to a H87M-Pro board that is fed by a 80+Gold PSU, despite its many 'bad sectors' I remembered from 2 years ago in a btrfs raid1 setup. This 500G disk has worked well for almost 2 years connected to a 7-inch eeepc4G, XFS formatted. But with the H87M-Pro I just now saw that it dropped off the USB every now and then, causing trouble for Btrfs. For connecting harddisks to phones, I once bought an external powered hub, and I put that between the board the the 500G disk => that made it all stable, no disconnects and Btrfs works fine as expected. I had similar issues on another PC with a Sandisk Extreme 64G USB3 stick, but that was likely a protocol issue. So maybe try to use the stick with your use case in another HW setup, hopefully then it is stable for a longer time than the few days now. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
