If your system is configured to perform an rsync backup as part of the standard snapshot script, simply run the following command:
at now -f /u2/UTILS/bin/snapsave_linux.sh
To schedule the backup at specific date and time, for example at 11PM today, change now to 23:00.
at 23:00 -f /u2/UTILS/bin/snapsave_linux.sh
This script will suspend your database, take snapshots of the database files and create a full tape backup. You will not see any output in your console session, because the script creates a separate log file under /tmp/snapsave.log.
If you have already created the snapshot filesystem, but you want to perform a separate manual tape backup:
rsync -avz --delete --stats /snap/u2/ /mnt/nas/rsync/
If there are no snapshots present, but no users are on the system and you want to perform a manual rsync backup:
rsync -avz --delete --stats /u2/ /mnt/nas/rsync/
References:
How to use the at command
How to use rsync