[CentOS] CentOS 4.4 - added disk prevents system from booting past initrd

Mon Apr 30 11:15:16 UTC 2007
Simen Thoresen <simentt at dolphinics.no>

Hi people,

I ran into one of these silly issues I'd like to share as I think the 
reason behind it may be a flaw in the current initrds.

The setup;
Dual-Xeon Intel-chipset motherboard. SATA-disk attached to ICH, onboard 
Adaptec SCSI-controller.

Installed system, updated packages, no problems. Basic, non-LVM 
partition setup - OS-disk is /dev/sda, single filesystem-partition 
/dev/sda1 is labeled LABEL=/, and fstab uses the label to access the 
filesystem.

I now add a SCSI-disk (previously used) to the onboard SCSI-controller, 
and the fun starts. The onboard controller is identified as scsi0 and 
scsi1, the SATA-disk sits on scsi2. SCSI-disk is thus /dev/sda, and 
SATA-disk becomes /dev/sdb. This should not be a problem as the fstab 
refers to the partition by label and not device name.

And then disaster! While booting, the system issues 'Checking root 
filesystem' (I'm not 100% sure about the output here), and craps out on 
a badly broken /dev/sda1. On the SCSI-disk, /dev/sda1 is an extended 
partition, with /dev/sda5 being the partition that holds the filesystem. 
Thus fsck'ing /dev/sda1 does not bring any useful. But why?

Why does the initrd insist on fsck'in /dev/sda1, when it should check 
LABEL=/?

Is there something I'm not getting here?

-S
-- 
Simen Thoresen, Dolphin ICS
Systems Administration and Wulfkit Support