SCSI troubles

[Sven Willenberger]

On Wed, 2005-07-06 at 00:29 -0700, Ade Lovett wrote:
> Niki Denev wrote:
> > From what i understand this is not exactly a FreeBSD problem, but rather
> > a consequence of U320 being really hard on the hardware with pushing it
> > to the limits.
> 
> Incorrect.  The relevant parts of the output you pasted are:
> 
> 	ahd
> 	Seagate drives
> 
> Attaching more than one Seagate drive to a single Adaptec chain will
> result in various weird and wonderful behavior as you've described.
> 
> This is above and beyond well known (and documented) issues with data
> loss and corruption with certain firmware revisions on Seagate drives.
> 
> You have essentially two options:
> 
> (1) disable the (on-board) adaptec controller, and use something else
> (LSI cards work pretty good)
> 
> (2) chunk the Seagate drives, and replace them with some other vendor
> (Hitachi, for example, in our high-stress environments, show equivalent
> MTBFs)
> 
We went with option 2 about a year or so ago (Hitachi drives in our
case) as dealing with Seagate on this issue turned into an exercise in
frustration (they suggested things like turning off SMP or using a PCI
network card instead of the onboard (em) network. As is pointed out the
issue really crops up with more than one seagate drive on the adaptec
(ahd) controller, even with the drives upated to their latest bios.
Switching to a different hard drive manufacturer solved our woes.

Sven