Backup HDD full - how to sync remainder to another HDD?

[theonematt]

So my main backup HDD is full, I want to sync the remaining data that isn't on the backup HDD to a second HDD - is this possible with freefilesync? Issue of course is ejecting one HDD and inserting another means the sync now thinks I haven't backed up the data. Any advice appreciated, thanks!

[xCSxXenon]

https://freefilesync.org/manual.php?topic=tips-and-tricks#copy-to-alternate-folder
You could have both backup drives connected, run a comparison between source and primary backup drive, then copy differences to a specified location, which is the second backup drive in your case.
Or search the forum for "one to many" or similar. One suggestion has been to split syncs up into groups of folders so each backup drive has a subset of the data

[therube]

I take it your sync is ongoing, yet can't go further, at this point, cause there is no space left for it to continue?

So like in floppy days, you want the backup to pause, prompt you to put in an empty floppy, then pick up from where it was.

Just thinking...

If FFS, flipped the (A)rchive bit (on a successful copy), & if FFS could select based upon the Archive bit being set...

How about, what is it, variable target locations. FFS does have that. Would that help?

What if you simply (Safely Remove) HDD1 (I suppose it is a "caddy" of some sort) & simply inserted HDD2 in its place, would FFS carry on from there?