I get this error when running parted on the internal drive:

Code:
~# parted /dev/mmcblk0
GNU Parted 3.4
Using /dev/mmcblk0
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) print                                                            
Error: The backup GPT table is corrupt, but the primary appears OK, so that will be used.
OK/Cancel?
I checked and gdisk/sgdisk is not installed. What is recommended way to rebuild the backup GPT from the primary table?