Use RSYNC to copy files

Check number of files in source folder

tree /source/folder | wc -l

Copy files from source to target folder

rsync -Pavzh --log-file=/tmp/copylog.log /source/folder /target/folder &

Display copy log

tail -f /tmp/copylog.log

Check number of files in target folder

tree /target/folder | wc -l

If the copy process being interrupted, repeat step 2 and the copying process will continue from the last state before interruption.