How does RSYNC "verify" integrity of a backup???

Can we get additional advice here on whether the FrontView Rsync does do the checksum?

Here is a post that makes it sound like it does. I just got SSH access to the RNPP unit, but am not familiar with the commands and the various options, so my preference is to use FV's Rsync option.

viewtopic.php?f=31&t=53612&p

PapaBear wrote:

Yes. Because of the verification process in rsync it is like watching paint dry to do a full backup with rsync. Setting it up as NFS creates the backup, and then rsync only has to verify the check figure for each file to make sure all the data is there. Then every time you run the rsync job, it only copies over the changed portions of the file, so the "incremental" is very fast. If you were going from X-86 to X-86 it would take less than 1/2 the time used by the Duo to X-86, (or X-86 to Duo) but we are still only talking minutes to update gigabytes of data. Yesterday I added about 40GB of video files to my NAS1, and checking the logs from last night, it took about 24 minutes. If this had been from my NVX to my NV+ I would anticipate it would take around 45-50 minutes. But, I don't add 40 GB of data very often.