Re: not all volume types export UUIDs (was: /dev/disk/by-id

[Kay Sievers <kay.sievers@vrfy.org>]

On Wed, 2008-07-02 at 12:28 +0200, martin f krafft wrote:
> also sprach Kay Sievers <kay.sievers@vrfy.org> [2008.07.02.1000 +0200]:
> > UUID's are the right solution here. Fix your mkswap, or re-run it, it
> > has support for this for long:
> 
> Yes, you are right, this does work for many of my cases.

> Unfortunately, there are still volume types out there without UUID
> support, such as LVM (I think), mdadm, and non-LUKS dm-crypt.

Then we should just add links for the raid-members. We already recognize
most of the metadata, just don't do anything with it.

> For
> those, UUIDs will not be available.

Oh, most of them have UUID's.

Anyway, the ID's are _bus_-id's, so the prefix is what we want. They are
in almost all cases unique on the same bus. Most devices which can move
from one bus to another will never share the same id's, like an
USB-storage device has no way to access ATA-data of the enclosed disk,
it will show the serial number of the usb-interface-device, which is
totally different.
ATA and SCSI are special, because of the Linux kernel using SCSI as a
transport for ATA, but we already create ata-* links for SCSI devices
which will show up if vendor=ATA, so this case is already covered.

What kind of id's do you have in mind, which would be the same across
buses?

Thanks,
Kay