Partition(s) on /dev/sda are being used

[Bernard Li]

Hello list:

I'm one of the developers of the SystemImager project:

http://wiki.sisuite.org/

SystemImager is an OS-imaging tool and we use parted to partition disks
prior to imaging.

We recently encountered an issue with parted and was wondering if the
developers can give us a hand.

While partitioning a disk (say sda), parted thinks that the partitions
are being used but in actual fact, it's not - here's the message we got:

parted -s -- /dev/sda mklabel msdos || shellout
Warning: Partitions(s) on /dev/sda are being used.
Killing off running processes.

I checked /proc/mounts, /etc/mtab and sda is not referenced there.  How
does parted determine if the partitions are being used or not?

The way we perform imaging is we first boot the system into an initial
ramdisk which we create, and the /dev comes from there.  Currently, we
prepare the ramdisk from a live Linux system and /dev is populated via:

        print ">>> Copying contents of /dev to new initrd...\n" if(
$verbose );
        $cmd = qq(rsync -a /dev/ $staging_dir/dev/);
        !system( $cmd ) or die( "Couldn't $cmd." );

So I wonder if /dev/sda rsynced this way is causing parted to behave
strangely.

Hopefully somebody can shed some light into this.  If any part is
unclear, please let me know.

Thanks in advance!

Bernard