SCSI vs SATA

SCSI vs SATA

[BuraphaLinux Server]

Hello,

    I have had a hard time determining if /dev/sda is SCSI or SATA
from my boot scripts.  It matters for smartd which needs an added
parameter -d sat in the configuration file for SATA drives.  Finally I
came up with this, but I wonder if there is a better way?  It appears
that
vendor is "ATA     " (5 trailing spaces) for SATA.  If the kernel is
ever fixed to show proper vendor information (Maxtor, Seagate,
whatever) then how can I know if /dev/sda is SCSI or SATA from a bash
script?  When flaming me, please also include the proper solution.
Thanks.

#!  /bin/bash
drive="sda"
vendor=$(</sys/block/${drive}/device/vendor)
if [[ "${vendor}" = "ATA     " ]]
then
  printf "SATA\n"
else
  printf "SCSI\n"
fi
exit 0

Re: SCSI vs SATA

[Michael Tokarev]

BuraphaLinux Server wrote:
> Hello,
> 
>    I have had a hard time determining if /dev/sda is SCSI or SATA
> from my boot scripts.  It matters for smartd which needs an added
> parameter -d sat in the configuration file for SATA drives.  Finally I

Just FYI:  Recent smartmontools (5.36+) can figure this out automagically.

/mjt

Re: SCSI vs SATA

[Rene Herman]

On 07/23/2007 12:52 PM, BuraphaLinux Server wrote:

> #!  /bin/bash
> drive="sda"
> vendor=$(</sys/block/${drive}/device/vendor)
> if [[ "${vendor}" = "ATA     " ]]
> then
>  printf "SATA\n"
> else
>  printf "SCSI\n"
> fi
> exit 0

This is probably not a useful comment and a reasonable script in your local 
setting but still thought I'd point out that these days most anything is 
sda, so if !SATA it can generally also be USB, or FW, or ...

Rene.

Re: SCSI vs SATA

[Robert Hancock]

BuraphaLinux Server wrote:
> Hello,
> 
>    I have had a hard time determining if /dev/sda is SCSI or SATA
> from my boot scripts.  It matters for smartd which needs an added
> parameter -d sat in the configuration file for SATA drives.  Finally I
> came up with this, but I wonder if there is a better way?  It appears
> that
> vendor is "ATA     " (5 trailing spaces) for SATA.  If the kernel is
> ever fixed to show proper vendor information (Maxtor, Seagate,
> whatever) then how can I know if /dev/sda is SCSI or SATA from a bash
> script?  When flaming me, please also include the proper solution.
> Thanks.
> 
> #!  /bin/bash
> drive="sda"
> vendor=$(</sys/block/${drive}/device/vendor)
> if [[ "${vendor}" = "ATA     " ]]
> then
>  printf "SATA\n"
> else
>  printf "SCSI\n"
> fi
> exit 0

libata follows the SAT standard for ATA device identification as a SCSI 
device, which specifies the vendor is always supposed to be ATA. 
Checking for vendor ATA is likely safe then, though if it's not you 
can't assume it's going to be SCSI as it could also be USB, IEEE1394, etc.

-- 
Robert Hancock      Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@nospamshaw.ca
Home Page: http://www.roberthancock.com/