Backing up the SD card

Begin by shutting down the BBB or RPi and removing the uSD card. Using the uSD to SD adapter in the BBB or RPi's box on the shelf, connect the uSD card to your computer. Using this process, you will need 32GB of temporary free space. Compressed, the image should be less than 2GB. There is a way to directly write the compressed version.

OSX

diskutil list
# Find the 32GB volume and take note of it. Should be something like /dev/disk2
# Now take that diskname and append 'r' to the front. For example, /dev/disk2 -> /dev/rdisk2
sudo dd if=/dev/rdisk2 bs=5m | pv -s 29G > sdimage`date +"%Y%m%d"`.img
# The 'pv' part can be omitted if progress is not needed. The process should take about 15 minutes
# Once done, the image can be compressed.