kernel panic on a 2950

[David_Kewley at Dell.com]

> -----Original Message-----
> From: linux-poweredge-bounces at dell.com [mailto:linux-poweredge-
> bounces at dell.com] On Behalf Of Kaj Niemi
> Sent: Tuesday, May 13, 2008 11:21 AM
> 
> On May 13, 2008, at 20:31, Chamberland, Robert wrote:
> 
> > Just before the RHEL rescue disk kicks in the controller correctly
> > reports seeing two logical drives.
> > The rescue disk reports not seeing the drives and asks if I want to
> > install drivers for them (which I skip).
> 
> Did you, by any chance, happen to boot with another kernel than the
> one you were running before rebooting? If the VDs aren't seen it could
> be that the initrd image does not contain the necessary drivers to
> talk with the card; this usually means mkinitrd got hosed when
> installing the new kernel.

Following up on Kaj's idea:

If you have an original 2950, the built-in RAID controller is PERC 5/i,
and its driver is megaraid_sas.  You need a line like this in
/etc/modprobe.conf:

alias scsi_hostadapter megaraid_sas

(If you have other scsi_hostadapter* lines, it might need to be
scsi_hostadapterN, where N is 1, 2, 3, 4,...)

Is it possible this line got removed when you were messing with NIC
configs?  If so, and if you manually or automatically updated your
initrd (automatic update could happen via a kernel or kernel module rpm
install/update), then the new initrd would not have the driver.  When a
boot is attempted using this initrd, it would not be able to locate your
hardware RAID, which means it could not access /.  This would match your
original kernel panic symptoms.
 
Do you have another kernel in GRUB that you can boot into?  Maybe its
initrd has the necessary drivers.

David


David Kewley
Dell Infrastructure Consulting Services
Onsite Engineer at the Maui HPC Center
Cell: 602-460-7617
David_Kewley at Dell.com

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