Something I wish I had known before buying a Synology for my needs:

https://duckduckgo.com/synology%20rsync%20issues%20acl?ia=web

They don’t use standard ACLs under the hood, which can interfere with some possible uses, mostly around rsync or extended attributes used by Macs and other Unix/Unix like systems.

Picked up a DS218play earlier this year to try and salvage what’s left of my old NASes. Open to selling/trading it to someone local if interested before I look at converting it to an iSCSI disk instead of a NAS.