MegaRAID 'Bad Slot' Kernel message and crash.

[Tony Byrne]

Hello Doug,

Friday, January 14, 2005, 1:35:16 AM, you wrote:

DW> scottl has been able to reproduce this on a U320 controller he has. I only
DW> have U160 equipment and can't get the txn rate up high enough to reproduce
DW> the issue.  The driver needs KTR instrumentation so we can see where the
DW> bad slot is popping up from.  The "bad slot" message appears when the
DW> controller returns completion for a command that had already completed.

DW> The amr driver has several other issues and is in dire need of an
DW> overhaul. Unfortunately LSI has not been forthcoming with documentation,
DW> so Scott and I are pretty much scratching our heads without knowing where
DW> to go.

DW> This is in 5.X and HEAD, at least.  I can't comment on 4.x.

We have switched off adaptive read caching on the card.  One of my
other correspondents has said that he hasn't been experiencing this
problem. He  sent me his configuration settings.  Only time will tell
if this helps.

What is state-of-the-art, regarding SCSI RAID support in FreeBSD?
Which cards / drivers are favoured for their stability?  We are
building a second server, initially without RAID, but given our
problems with amr we are considering another RAID controller supported by a
different driver.  We want to do write caching and need a card that
supports a battery backed cache.  How about the Adaptec cards?

Regards,

Tony.

-- 
Tony Byrne