Before booting the BeagleBone Black for the first time, you may want to snap an image of the unbooted the Angstrom load from NVRAM in its virgin state for future reference. To do this, we need a microSD card to boot the BeagleBone Black and snap the image. The BeagleBone Black Ubuntu image available on the downloads page will work nicely for this purpose. Just cat the image using these instructions, then boot it from microSD by holding down the user button at power-on. Once booted, ssh into the device, sudo su to root, and get started.
If you need the original image you can find it located on the downloads page.
The internal NVRAM will be seen as the /dev/mmcblk1 device.
# ll /dev/mmcblk*
brw-rw---- 1 root disk 179, 0 Apr 30 03:24 /dev/mmcblk0
brw-rw---- 1 root disk 179, 1 Apr 30 03:24 /dev/mmcblk0p1
brw-rw---- 1 root disk 179, 2 Apr 30 03:24 /dev/mmcblk0p2
brw-rw---- 1 root disk 179, 8 Apr 30 03:24 /dev/mmcblk1
brw-rw---- 1 root disk 179, 16 Apr 30 03:24 /dev/mmcblk1boot0
brw-rw---- 1 root disk 179, 24 Apr 30 03:24 /dev/mmcblk1boot1
brw-rw---- 1 root disk 179, 9 Apr 30 03:24 /dev/mmcblk1p1
brw-rw---- 1 root disk 179, 10 Apr 30 03:24 /dev/mmcblk1p2
Capture the image using the dd command.
# dd bs=1M count=1832 if=/dev/mmcblk1 | xz -cz > ./bbb_angstrom_ga.tar.xzNow is a good time to go get a cup of coffee because this takes a while.
In the future if you need to restore the image, just do the reverse:
# xz -cd ./bbb_angstrom_ga.tar.xz > /dev/mmcblk1