Can I wake up external power management disk enclosure properly?

nac.zero · 06-21-2009, 02:09 AM

I have a 1TB hard drive and power management disk enclosure connected to a linux box(2.6.19) via USB. The enclosure can turn off by itself if no access to the drive for 5 min.

But data access to powered off enclosure can be failed and the linux box senses I/O error like this (dmesg);

Code:

sd 2:0:0:0: Device not ready: <6>: Current: sense key=0x2
    ASC=0x4 ASCQ=0x2
end_request: I/O error, dev sda, sector 0
Buffer I/O error on device sda, logical block 0
Buffer I/O error on device sda, logical block 1
Buffer I/O error on device sda, logical block 2
Buffer I/O error on device sda, logical block 3

And then if the disk enclosure wakes up properly I can access data on the drive.
Though sometimes data access is delayed or failed continuously.

Is there any way to wake up the enclosure without I/O error?
Or is there any way to handle the enclosure?
I found topics about hdparm and sdparm command to spin down hard drive, it might be helpful, but I could not find good way to handle it with the commands.
Thanks in advance.

nac.zero.

farslayer · 06-22-2009, 08:19 AM

I know there were issues with certain external USB Hard drives.. you should list exactly what it is you have, there may already be a fix or workaround available if you have one of those specific units.

wow, still running a 2.4 kernel..

nac.zero · 06-22-2009, 06:00 PM

farslaye, thank you for your comment.

Oops, 2.6.19 is correct, kernel2.4 is not correct, just typo.

And I use Logitec HDD READER WRITER, LHR-DS02SAU2RD and Hitachi HDT721010SLA360
(Logitec enclosure might be available in Japan, only. So I didn't list its unit name or type. Sorry.)

Thanks.

nac.zero · 08-03-2009, 08:31 AM

I found a solution. That is using allow_restart under /sys parameter to wait spin up properly.
I set it to 1 and then it works well.
See also here for detail;
http://forums.opensuse.org/archives/...ev-10-3-a.html