* Will Mengarini <sel...@eskimo.com> [24-10/03=Thu 19:57 -0700]: > I have a freshly installed Debian stable and I'm trying to read an > HDD from a previous machine. I put it into a disk enclosure that > connects to the new machine by USB and powered everything up, but the > stable Debian doesn't see the new disk that is connected by USB.
There were several suggestions that the enclosure may not have been receiving enough power, and I think that it was not, although I didn't realize this until I had put the enclosure away and started to attempt restoring from an old backup on an external HDD. Initially that HDD (my only recent backup) could not be mounted because of continuous errors. However, prompted by the discussions in here about power, I tried a different power strip, and noticed that on that power strip there was a transformer for a pair of speakers that had worked correctly until the machine I was backing up from had crashed, but now did not seem to be working correctly because their power LED was always off. That seemed strange, so I removed the transformer for that pair of speakers since they didn't work anyway, and suddenly the hard disk drive from which I was restoring was able to be mounted. I am using rsync to restore from it now. The power strips were chained, so it seems plausible that a failed pair of speakers connected to one power strip was drawing enough power although doing nothing that it was preventing the hard disk drive on a different power strip from receiving enough power to spin up properly. Once the transformer for the speakers was unplugged, the hard disk drive was able to spin up and I was able to restore from backups. The reason this is only "maybe" solved is that I haven't yet gone back to the hard disk enclosure that was the original subject of this thread. Instead I'm restoring from a different external hard disk drive which also was failing until the transformer for the speakers was removed. I conjecture that eventually I will be able to read from the hard disk drive enclosure containing the latest data, but first I will finish my current restoration from backup. This is a wild war story. I would not have expected a failing pair of speakers to be able to draw enough power to prevent a disk drive on a chained power strip from receiving enough power. It may actually be the case that what really mattered was that those speakers were plugged in to the rear panel of the desktop computer that I was setting up, and perhaps they were drawing too much power from there. I cannot think of an easy way to test that hypothesis without endangering this hardware, which I do not want to do. A hmm-worthy observation is that in order to get this new computer to work I needed to plug it into an old LCD monitor (Viewsonic VX2025wm) that has its own built-in speakers. I wonder whether there is some operating system bug that can cause trouble when external speakers are plugged into a computer that also has speakers built into the monitor. Many thanks to everybody who participated in this thread and gave me suggestions.
