Re: SCSI device probing non-deterministic in 5.3

From: Bradley LaBoon
Date: Tue Oct 08 2019 - 16:20:09 EST




On 10/4/19 11:39 AM, Bart Van Assche wrote:
> Have you already had a look at the /dev/disk/by-path directory? An
> example of the contents of that directory:
>
> $ (cd /dev/disk/by-path && ls -l | grep /s)
> lrwxrwxrwx 1 root root 9 Oct 3 16:49 pci-0000:00:02.0-ata-1 -> ../../sda
> lrwxrwxrwx 1 root root 9 Oct 3 16:49 pci-0000:00:08.0-scsi-0:0:0:1 ->
> ../../sr0
>
> Have you considered to use these soft links in /etc/fstab?
>
> In case using these links would be impractical: have you considered to
> add a udev rule that creates H:C:I:L soft links under a subdirectory of
> /dev, that makes these soft links point at the /dev/sd* device nodes and
> to use these soft links in /etc/fstab? That's probably a much more
> elegant solution than what has been proposed above.
>
> As one can see the information that is needed to implement such a udev
> rule is already available in sysfs:
>
> $ (cd /sys/class/scsi_device && ls -ld */device/block/*)
> drwxr-xr-x 9 root root 0 Oct 3 16:48 2:0:0:1/device/block/sr0
> drwxr-xr-x 9 root root 0 Oct 3 16:48 3:0:0:0/device/block/sda
>
> Bart.

Thanks for the reply! I wasn't aware that sysfs exposed the mapping that
way. That is very useful, and we should be able to utilize that.

Regards,
Bradley LaBoon