TL:DR: I have a Synology NAS with a huge set of source files and a second (target) NAS with a duplicate of these files (plus a few days work). I would like to copy the Creation Timestamp from the source files to the target files.
Long story:
My work recently had a hard drive fail within one of our Synology NASs. Working off of a backup, I decided to update our backup strategy, which involved a new NAS and new drives. I set up our backup NAS to use Synology's Folder Sync functionality to create my duplicate files on the new NAS. It worked great except for one thing.
The files on the new NAS took their modification timestamps from the source files just fine, but the creation timestamp was set to the day that I did my backup for every single file. Some of my coworkers use the file creation timestamp for their work, so I"m trying to get the correct timestamps back.
In the past, I've updated modification timestamps by writing a PHP page that simply looked through both file trees for matching filenames, overwriting modification timestamps as it went, but I can't figure out how to do this with creation timestamps, or even if it's possible. Also, the modification timestamps on the target files are all correct. There are tens of thousands of files on the drives, so updating one by one is not possible. What are my options? Is it possible?
Edit: Since people have asked, my NAS is reporting the filesystem to be "Btrfs". It has 4 drives in it set up in RAID 10.