PING will not backup /dev/mapper/systemVG-LVRoot

All,

I am trying to find a few answers about PING.  I am trying to make a complete backup of my RSA 3.0 Authentication Manager Appliance running v8.1 SP 1 Patch 11 file system.

Filesystem Size  Used Avail Use% Mounted on

rootfs 449G  4.8G  422G 2% /

udev 2.0G  164K  2.0G 1% /dev

tmpfs 2.0G     0  2.0G 0% /dev/shm

/dev/mapper/systemVG-LVRoot 449G  4.8G  422G 2% /

/dev/sda1 1008M   52M  906M 6% /boot

I received an error when I attempt to save the /dev/mapper/systemVG-LVRoot to a external USB drive.  PING displays a screen saying “save partition to image file” then goes back to the >> prompt

Thank you,

1. T.J.