I installed Debian Lenny on my eSata Sheevaplug, by strictly following Martin Michlmayr's guide. Next, I attached to it a self-powered external eSata enclosure, with a Samsung Sata drive inside.
My problem is that, after some time of disk inactivity (or so it seems), the drive seems to spin-down by itself, or enter a sleep state, or similar; and the OS is obviously unaware of this.
Result: strange I/O errors, with “no such file or directory” errors on read attempts, and file listings full of “?” instead of the usual “rwx”, and so on. Restarting the Sheevaplug does not help. Restarting the Sheevaplug AND the external drive, though, leads to normal behaviour again.
I found a cure to this problem: every hour, CRON runs:
“sdparm --command=start /dev/sda”
I've read that a disk can accept only a finite number of spin-ups/downs, so I later changed crontab to run the command every 10 minutes instead.
___ Now the reason for this post. ___
I'm not very satisfied with the current situation, because:
— I'd rather enable the drive's power-save features, which will help bring down power consumption, and noise, and wear.
— I actually fear that this constant “start” command on the drive may be bad for it.
So is there a better solution?