Re: [opensuse] Re: Large disks in Opensuse 11

On Wed, May 6, 2009 at 4:47 PM, Randall R Schulz <rschulz@xxxxxxxxx> wrote:
On Wednesday May 6 2009, Larry Stotler wrote:
On Wed, May 6, 2009 at 2:18 PM, Randall R Schulz wrote:
...

However, whether a drive is connected by SATA, eSATA, USB,
FireWire, SCSI, SAS or IDE / ATA, it is still and equally
"directly" connected.

Not if there is some other problem.

I guess I don't know what you mean by "direct." In all these cases there
is an electrical connection between the device and the computer that
conveys power and the control and data signals. What can be
more "direct" than that?

Well, usb is a scsi protocol transport (T10), not a ata protocol
transport (T13).

So the linux kernel sends scsi commands to the usb adapter. It has a
SAT device (scsi to ata translator) that turns those into ata commands
and sends those to the drive.

So a bug in the SAT device can cause the drive to not work correctly.
I don't consider that a direct connection.

Greg
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