[SLL] /dev/sd names not in motherboard order

[Bryan McLellan]

On Mon, Mar 2, 2009 at 12:27 PM, Mathew D. Watson
<watson at visiongate3d.com> wrote:
> I now think that this command may be responsible for assigning the device
> names. Actually, I think "may be" is weak, but my knowledge about this is
> slim to none.

All nodes in /dev are created by udev now. There's some magic with
/dev/.static/dev, which I can't explain off the top of my head. These
used to be special files that could be recreated manually with mknod.
file in /dev have a major and minor device number which you can see
from the ls -l output, which you would previously pass to mknod.

On Mon, Mar 2, 2009 at 11:34 AM, Derek Simkowiak <dereks at realloc.net> wrote:
>   Note, UUIDs are not the factory "serial number" of the hard drive.  It's
> just a random ID number that written onto the disk, in the partition table.
>  You can change the UUID to a new value with "tune2fs -U".  (You can see
> your UUIDs with "blkid".)

Adding to what Derek said, your UUID should be created when you format
a partition, providing that mkfs tool supports it. It is randomly
generated and written inside the partition, so using dd to copy the
partition or disk will end up with the disk having the same UUID.

Since the disk may move around in respect to /dev/sd*, Ubuntu uses the
UUID to determine the device + partition. You can run '/sbin/blkid' to
see the UUIDs on the disk. Ubuntu then mounts the disk + partition
with the corresponding UUID.

Since the UUID gets copied when you dd a disk, you shouldn't use
/dev/disk/by-uuid to script dd. Since your physical disks aren't going
to be replaced very often, I would use /dev/disk/by-id.