linuxgeek: [nslu2-linux] Debian Slug USB issues

Thursday, May 6, 2010

[nslu2-linux] Debian Slug USB issues

Hi,

I've run my Slug with Debian Lenny relatively trouble-free for some time. A month or so ago however it failed booting from the attached 2.5" USB HDD (bus-powered). After replacing that disk with a self-powered 3.5" USB HDD all was fine again. When I was trying to find the cause for that problem, I did discover that plugging a new power supply into the Slug made it recognize the old HDD. So I guess the power supply couldn't provide the power to the USB port anymore.

Anyway, all was fine until about a week ago when one of my Slug drives was stuck in the middle of a backup: no i/o anymore. I found USB related errors in the log files.

This is what my setup looks like:

SLUG -> USB1 -> 3.5" HDD (self powered - Boot volume)
|-> USB2 -> 4 port bus powered Hub -> 3.5" HDD (self powered)
|-> 3.5" HDD (self powered)

What happens is that whenever I plug in a USB Hub (I've tried 2), the Slug fails to boot. Even if the boot disk is plugged directly into the Slug. If I plug in the USB Hub after boot, I get all kinds of USB errors, e.g. unable to enumerate USB device on port x in kern.log.

Could all of this be a sign that the Slug power supply is dying?

Would it be safe to use a powered USB Hub with the Slug? I remember that when I once tried this, it seemed the Hub was also powering the Slug itself (USB power flowing back into the Slug?).

If it is the power supply, what would be a good replacement? It seems this particular voltage and plug is not very common.

Thanks in advance for your help/tips/suggestions.