Re: [gentoo-user] cannot open root device "sda3"

[Alan McKinnon]

On Thursday 21 January 2010 20:08:53 Valmor de Almeida wrote:
> Hello,
>
> I am trying to boot gentoo from an external USB HDD.  I am getting the
> error message:
>
>   VFS: Cannot open root device "sda3" or unknown-block(2,0)
>   Please append a correct "root=" boot option; here are the available
> partitions:
>   Kernel panic - not syncing: VFS: Unable to mount root fs on
>  unknown-block(2,0)

This almost always means that you don't have a required module compiled into 
the kernel and are not using an initrd.

Common modules are the motherboard chipset and the fs on the disk


>
> I am assuming that the device will be named /dev/sda since there is no
> other HDD on the system. The message above does not list any available
> partitions.
> Any thoughts?
>
> Here is the info from fdisk on this drive (it is a new 4096-byte sector
>  drive):
>
>   Disk /dev/sdb: 240.1 GB, 240057409536
>   255 heads, 63 sectors/track, 29185 cylinders
>   Units = cylinders of 16065 * 512 = 8225280 bytes
>   Disk identifier: 0x0c7786a9
>
>   Device       Boot     Start     End        Blocks       Id  System
>   /dev/sdb1     *              1       26        208813+    83  Linux
>   /dev/sdb2                   27     158      1060290      82  Linux
> swap / Solaris
>   /dev/sdb3                 159    2117    15735667+    83  Linux
>   /dev/sdb4                2118  29185  217423710      8e Linux LVM
>
> Thanks,
>
> --
> Valmor
>

-- 
alan dot mckinnon at gmail dot com