I'm using the scsi/sata to handle an IDE dvdrw and a SATA dvdrw. I get two
devices named /dev/sr0 and /dev/sr1.

Normally the IDE dvdrw goes to /dev/sr0 and the SATA dvdrw goes to /dev/sr1.
So far so good.

The problem is that about one reboot in twenty, the devices get reversed.
/dev/sr0 is assigned to the SATA drive and sr1 to the IDE drive. This is
a major PITA. Is there any way to fix the assignments?

AZ Nomad wrote:

> I'm using the scsi/sata to handle an IDE dvdrw and a SATA dvdrw. I get
> two devices named /dev/sr0 and /dev/sr1.
>
> Normally the IDE dvdrw goes to /dev/sr0 and the SATA dvdrw goes to
> /dev/sr1. So far so good.
>
> The problem is that about one reboot in twenty, the devices get reversed.
> /dev/sr0 is assigned to the SATA drive and sr1 to the IDE drive. This is
> a major PITA. Is there any way to fix the assignments?

Yes, by manually including entries for them in your /udev/ configuration
file(s). Not that I've ever done this myself - I'm new to /udev/ myself,
actually - but I know it is possible via the information for each device
under the */sys* and/or */proc* trees.

If I understand correctly, then it would be similar to using a NIC's MAC
address for assigning an IP address to it. You would thus use
hardware-specific strings to tell /udev/ which device needs to be
*/dev/sr0* and which device needs to be */dev/sr1.*

I believe I'll be up to that task myself - not that I am in the habit of
rebooting any of my machines - because my one machine has an SATA Plextor
DVD-writer and a USB Iomega REV drive, which is seen by the kernel as a CD
device - it's actually a kind of removable hard disk, similar to the old
Iomega Jaz but smaller in size and much larger in storage capacity.

Hope this helps... ;-)
--
Aragorn
(registered GNU/Linux user #223157)

AZ Nomad wrote:

> I'm using the scsi/sata to handle an IDE dvdrw and a SATA dvdrw. I get
> two devices named /dev/sr0 and /dev/sr1.
>
> Normally the IDE dvdrw goes to /dev/sr0 and the SATA dvdrw goes to
> /dev/sr1. So far so good.
>
> The problem is that about one reboot in twenty, the devices get reversed.
> /dev/sr0 is assigned to the SATA drive and sr1 to the IDE drive. This is
> a major PITA. Is there any way to fix the assignments?

Try this:

http://www.reactivated.net/writing_udev_rules.html

Just find something that identifies each device uniquely (eg by using
udevinfo or looking into /dev/disk/by-id), and write appropriate udev rules
to create symlinks.