I have a 5TB external drive. I want to have multiple partitions. without using gparted, which i have been having problems with, how do i format using the mkfs.ext4 format to create 3 partitions? part1=2TB, part2=2TB, and part3=1TB. The smaller drives I can format no problem. i am using mkfs.ext4 -L black5 /dev/sdj.