How can files in ubuntu server /opt/backups/ directory be automatically backed up to U disk in increments every day

  docker, question 
I installed gitlab with docker on ubuntu server14.04, and then the gitlab files set in docker are automatically backed up to /opt/backups every day.  However, because the ordinary computer used is not a server server, the boss is worried that the hard disk is easy to break down, so he bought a U disk.  Then prepare to back up the files in the /opt/backups directory to the U disk automatically every day. The U disk has been mounted under the /mnt/usb directory.  Since I am a front-end worker, I don't know much about shell.  Do you want to know how to do it?

Thank you!

Can write a script, convenient backup at any time
The first step is to write a script that can back up files to the U disk.
For example: backups.sh

tar cvzf /mnt/usb/$(date +%Y%m%d%H%M%S).tar.gz /opt/backups

The second step is to use cron to automatically execute the backup script.

$ sudo crontab -e
0 17 * * * /bin/bash /where/is/your/backups.sh
 #17: 00 Automatic Backup:

Or directly use crontab -e ：#17 to perform backup automatically:

0 17 * * * tar cvzf /mnt/usb/$(date +%Y%m%d%H%M%S).tar.gz /opt/backups