When I set up Robocopy some years ago, I initially thought that the subsequent sync. operation had failed, because it completed so quickly. Some testing showed that it was working as intended, and even 1Gb of test data was added in a few seconds. Typically, we run the backup at the end of the day to save vital files that previously might have been copied to an emergency thumb drive.
Robocopy seems not very user friendly and only for those with significant cpu knowledge background. Not sure, even the computer savvy person would use that. I took a look a while ago and then again now when you just mentioned, and just seems like too much work/trouble to go through and assure it runs and sets up.
It may seem that way, but mostly because it has lots of options.
Nice thing about robocopy is that there are tons of examples out there to work from. Here is mine. It runs from a Win11 PC every night at 2am using Windows Scheduler. It copies data (newer only) from two different drives on the PC, and several folders under those drives. It maps a drive letter (Q) to my NAS, then it copies data all night. I too got confused by some of the options, so at some point I took the time to document them within the batch file.
***
rem old Q:=\\CJCbackupQNAP\backup <---this refers to my old NAS.
rem net use q: \\192.168.101.97\nas_images
rem Q:=\\Supernas2\multimedia2 <-the NET USE command maps a drive letter.
net use q: \\Supernas2\multimedia2
robocopy d:\downloaderpro Q:\downloaderpro /MT:64 /R:2 /E /XO /TIMFIX /FFT /xf d:\pagefile.sys /xd d:\database d:\nxcache d:\temp d:\temp2 d:\$recycle.bin d:\recycler "d:\System Volume Information"
robocopy d:\webpages Q:\webpages /MT:64 /R:2 /E /XO /TIMFIX /FFT /xf d:\pagefile.sys /xd d:\database d:\nxcache d:\temp d:\temp2 d:\$recycle.bin d:\recycler "d:\System Volume Information"
robocopy d:\videos Q:\videos /MT:64 /R:2 /E /XO /TIMFIX /FFT /xd "c:\System Volume Information"
robocopy d:\working q:\working /MT:64 /R:2 /E /XO /TIMFIX /FFT /xd "d:\System Volume Information" d:\pagefile.sys
robocopy e:\photos Q:\photos /MT:64 /R:2 /E /XO /TIMFIX /FFT /xf d:\pagefile.sys /xd d:\database d:\nxcache d:\temp d:\temp2 d:\$recycle.bin d:\recycler "d:\System Volume Information"
robocopy c:\Users\Craig\Documents\ifolder39 Q:\Users\Craig\Documents\ifolder39 /R:2 /E /XO /TIMFIX /FFT /xd
robocopy r:\intranet Q:\intranet /R:2 /E /XO /TIMFIX /FFT /xd "r:\System Volume Information" r:\pagefile.sys
rem /E=copy subdirectories, including empty ones
rem /XO=exclude older files (only copy newer ones if same name)
rem /TIMFIX=fixes file times on all files, even skipped ones
rem /FFT=assumes Fat File Times (2-second precision)
rem /xd=eXclude Directories
rem /R:2=only two retries on a failure (default is 1 million)
rem /MT:64=enable 64-bit multithreading
***
To understand more of the above, it is useful to know that I use a D drive as a working drive, with folders for freshly downloaded images and videos on that drive. Once done post-processing files, I move them inside Lightroom from the D drive to my E drive. Robocopy does both drives. Once my data hits the NAS, there is a program running on the NAS that syncs the data to a second, older NAS.