AWS S3 sync will have a capability of resume upload and download.
To upload Local to S3:
nohup aws s3 sync /opt/thirumal/ s3://thirumal-bucket/ > /home/ubuntu/thirumal.log 2>&1 &
with sudo,
Export credentials
export AWS_ACCESS_KEY_ID=XXXXXXX
export AWS_SECRET_ACCESS_KEY=XXXX
Run command with sudo
nohup sudo -E aws s3 sync /opt/thirumal/ s3://thirumal-bucket/ > /home/ubuntu/thirumal.log 2>&1 &
To Download S3 to Local:
nohup aws s3 sync s3://full-backup/ /opt/thirumal/ > /home/ubuntu/thirumal.log 2>&1 &
Check the running jobs by typing
jobs