[CentOS] 3ware disk failure -> hang

[Bryan J. Smith]

Adam Gibson <agibson at ptm.com> wrote:
> The port0 error was after every crash.

Check your cable.  Check your tray if you have one.

The issue I've typically seen with 3Ware PATA setups I
haven't installed is a cheap tray.  SATA solves much of this
issue, but you can still run into it.

> I would not feel right trying to report this to RH
> bugzilla.  Is that something that has been done in the
past?

Yes.  Any issue should be reported to Bugzilla -- Fedora Core
or Red Hat Enterprise Linux (CentOS).  In fact, I recently
had a RHEL issue and Red Hat explicitly told me to run a
newer Fedora Core version (with a newer kernel or set of
kernel patches) to see if it fixed the problem.  If so, then
they'd integrate those fixes into the next RHEL update, or at
least tell me what to patch in.

> I am just really surprised that RH has not found this
problem
> on their own.  3ware controllers are used by a lot of users
I
> would think.  To have a problem like this is a pretty big
deal
> I would think.

There are countless hardware and software RAID issues on a
regular basis.  Just hit Bugzilla and you'll see.

For the most part, knowing _how_ to deploy hardware or
software RAID is the critical factor.  If you use 3Ware, use
its facilities.  The biggest falicy I see propogated is that
you can use its hot-swap and fault-tolerance with software
RAID.  You can't any more than any other ATA or SCSI card
I've used (although I have to investigate some of the SCSI
cards people are using here).

If you need RAID-5 write performance, do _not_ use the 3Ware
Escalade 7000/8000 cards.  They only have a measly 1-4MB of 0
wait state SRAM (static RAM) and operate as a "storage
switch" and are _not_ a "buffering controller."  Consider
RAID-10 instead, which it excells at, especially since it's
write performance is far, far better than any RAID-5 write
I've seen (software or hardware).

A few people here are running the newer 3Ware Escalade 9500S
cards with firmware 9.2.1.1, an updated driver to match
(newer than what the stock/Red Hat kernels are running with)
and RAID-5 with good results.  I haven't personally used
these, as I still prefer to deploy RAID-10 on the 8000
series.  I've heard the 9550SX is still maturing.


-- 
Bryan J. Smith     Professional, Technical Annoyance                      b.j.smith at ieee.org      http://thebs413.blogspot.com
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*** Speed doesn't kill, difference in speed does ***