Re: Serial ATA (SATA) for Linux status report

[Samuel Flory <sflory@rackable.com>]

Jeff Garzik wrote:
> Andre Tomt wrote:
> 
>> On Wed, 2003-12-03 at 21:44, Jeff Garzik wrote:
>>
>>> Intel ICH5
>>> ----------
>>> Summary:  No TCQ.  Looks like a PATA controller, but with a few added,
>>> non-standard SATA port controls.
> 
> 
>> One question - with "including hotplug", does that mean some set hotplug
>> standard? Reason I'm asking is, we have a few servers from SuperMicro,
>> with a ICH5R S-ATA controller that claims it's supporting hotplug, but
>> hotplug is not in your ICH5-summary.
> 
> 
> Alas, there is no hotplug support in the ICH5 or ICH5-R SATA hardware.
> 
> One could argue there is "coldplug" support in that hardware -- disable 
> the entire interface, including any active devices, then re-enable and 
> re-scan -- but it's a bit of a hack.  If there's enough demand, I could 
> write some code for that.  It would involve something like
> 
>     # /sbin/sata off
>     { plug in or remove a device }
>     # /sbin/sata on
> 
> You really, really, really don't want to actually unplug a SATA drive 
> while it's active, on ICH5 hardware.
>

   In theroy the scsi driver allows you kill a drive, and do rescan by 
echoing to /proc/scsi.scsi.  I know it worked under 2.4 with sca drive 
on a hotswap backplane.  This was over a year ago.  So it may have been 
broken.

scsi.c:
  * Usage: echo "scsi add-single-device 0 1 2 3" >/proc/scsi/scsi
          * with  "0 1 2 3" replaced by your "Host Channel Id Lun".


         /*
          * Usage: echo "scsi remove-single-device 0 1 2 3" >/proc/scsi/scsi
          * with  "0 1 2 3" replaced by your "Host Channel Id Lun".
          *

PS-  Yes I know says it isn't for hotswap, and that it's prebeta.  This 
comment dates back to at least 2.2.  It's worked for least 4 years.
-- 
There is no such thing as obsolete hardware.
Merely hardware that other people don't want.
(The Second Rule of Hardware Acquisition)
Sam Flory  <sflory@rackable.com>