As far as my German knowledge allows me to understand, the “412” has this folder set to “Receive Only” and has 631 files locally changed (0 Bytes of change, but still the same number of files in total, so they are not deleted - renamed, perhaps?). The “1815” machine is aware that “412” does not have these 631 files, so it shows them as not synchronized with “412”.
That’s exactly the question: why does Syncthing on 412 think that the 631 files on 412 have changed? What happened to these files on 412?
Again, here’s what happens: Syncthing on 412 sees that these 631 files it has locally on the hard disk are not the same as on the other machine. You need to investigate and understand how 412 changed these files and why.
That’s exactly the big question you need to figure out. I don’t really know what happened on server exactly, but I have seen similar situations when files got renamed unexpectedly. For example, the filesystem changed all " " (space) symbols to “%20”…
If the peer is read-only, what happens is exactly what you’re seeing: the peer that made these changes will have “local changes” (“Lokale Änderunden”), and the other peers will see that that peer has unsychronized files. If the peer is read-write (default), it will send these changes to other peers.
I have now set both peers to “Send & Receive” and the 631 files have been balanced. Not finally logical for me.
Yesterday both servers were on “Current”. My servers are shutting down for some hours in the night and start up in the early morning automatically.
Today I have one “Current” and the other in the status shown at 85%, for some time without change. No files are changed since yesterday evening, so its not clear that situation. Also all the peers are green, it means actual.