Re: dell poweredge 2400 harddisks going into offline mode when heavy I/O occurs

From: Matt Domsch
Date: Thu Sep 28 2006 - 11:13:28 EST

On Thu, Sep 28, 2006 at 04:19:23PM +0200, Folkert van Heusden wrote:
> Hi,
> I have a Dell Poweredge 2400 with 6 scsi harddisks in (hw-) raid 5.
> 512MB ram, 2x P3.
> When heavy disk i/o occurs, the system puts the harddisks into offline
> mode causing the filesystems to be put in readonly. The current kernel
> is 2.6.8, with 2.4.27 this did not occure. Googling did not help. The
> disks all have green lights (there's a special led for each to indicate
> errors - that one is off).

> Sep 28 16:05:12 kasparov kernel: aacraid: Host adapter reset request. SCSI hang ?
> Sep 28 16:06:12 kasparov kernel: aacraid: SCSI bus appears hung
> Sep 28 16:06:12 kasparov kernel: scsi: Device offlined - not ready after error recovery: host 1 channel 0 id 0 lun 0

Yes, this is familiar. See:

In addition, please consider mounting your file systems with
'noatime', as this reduces the number of small writes being sent to
the disks.

2.6.x kernels have the ability to swamp the RAID controller firmware
with requests where 2.4.x kernels couldn't so easily.


Matt Domsch
Software Architect
Dell Linux Solutions &
Linux on Dell mailing lists @
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