immenent disk failure ?

[Brian Fundakowski Feldman]

On Fri, Apr 15, 2005 at 10:10:52AM -0400, Bill Vermillion wrote:
> On or about Fri, Apr 15, 2005 at 12:01 , while attempting a 
> Zarathustra emulation freebsd-hackers-request at freebsd.org thus spake:
> 
> 
> 
> > Message: 4
> > Date: Thu, 14 Apr 2005 10:58:02 -0500 (CDT)
> > From: "H. S." <security at revolutionsp.com>
> > Subject: imminent disk failure ?
> 
> ...
> 
> > I have a server running 4.X for almost two years now, without
> > problems - rock solid as it should be - yesterday the server
> > became unresponsive, now that I have access again, and while
> > checking the logs, I found this as the last message before the
> > unresponsiveness:
> 
> > /kernel: ad0: READ command timeout tag=0 serv=0 - resetting
> 
> > The next message is the system getting back on, 1hour later.
> 
> > I have not changed anything kernel-related on this system for
> > a long time (jul 2004), just apply the occasional kernel patch
> > and rebuild/reboot the system. I never encountered this problem
> > before. Could this message mean this disk is giving its last
> > breaths ?
> 
> It might help if we knew a bit more about the system such
> a drive make and model - you can see that in dmesg.  That may
> point out some device that is known to be problematic.
> 
> The last time I got timeout errors like that was in the 3.x era
> with a SCSI controller.   Last IDE problem I had was a bad read
> that force the system into PIO mode with over 75% performance
> decrease.   The only way around that one that I was aware of was a
> reboot.

For any disk within perhaps the last five years you should be able to
just use SMART to perform a thorough health test on your hard drives
and view their statistics and error logs.  I don't know why it doesn't
currently do much on SCSI, but ports/sysutils/smartmontools works
great for ATA.

-- 
Brian Fundakowski Feldman                           \'[ FreeBSD ]''''''''''\
  <> green at FreeBSD.org                               \  The Power to Serve! \
 Opinions expressed are my own.                       \,,,,,,,,,,,,,,,,,,,,,,\