Taken from: https://superuser.com/questions/177823/are-there-any-tools-in-linux-for-splitting-a-file-in-place
Save following as ./splitmb.sh:
#!/bin/bash
# (c) whitequark 2010
# (c) dertalai 2015 (minimal modifications)
set -e
if [ $# != 2 ]; then
echo "Usage: $0 "
echo " This script will split file to multiple parts, starting from"
echo " the end, and truncating the original file in process."
echo " Part size is specified in megabytes (1 MB = 1048576 bytes)."
echo " Use at your own risk."
exit 0
fi
filename=$1
#partsize=$2
partsizeMB=$2
partsize=$(($2 * 1048576))
size=$(stat -c '%s' "${filename}")
parts=$(($size / $partsize))
do_split() {
_part=$1
_size=$2
echo "Splitting part $_part"
echo $(($partsize * ($_part - 1)))
dd if="${filename}" of="${filename}.$(printf '%04d' $_part)" \
count=$partsizeMB bs=1M skip=$((($_part - 1) * $partsizeMB))
echo "Truncating source file"
truncate "${filename}" --size="-$_size"
}
lastsize=$(($size % $partsize))
if [ $lastsize != 0 ]; then
do_split $(($parts + 1)) $lastsize
fi
for i in $(seq $parts -1 1); do
do_split $i $partsize
done
rm "${filename}"
make executable
Split into 100GB chunks: ./splitmb.sh ./huge.file.bin 100000
while true; do size=`du -sh -B1G ./directory | cut -f 1 | cut -d '.' -f 1 | cut -d 'G' -f 1`; echo -n "$size "; if [[ $size -gt <gigs> ]]; then printf 'yes\n\a'; else printf 'no\n'; fi; sleep 60; done