Yesterday, 02:00 PM
Yes, you can absolutely set this up the way you described. The simplest structure is to give each house its own NAS with two main areas. One private space for each user so their phone backups stay local, and one shared space that everyone in both houses can see. The shared folder is the only part that needs to stay synced between the DS425+ in house A and the DS918+ in house B.
Synology gives you several ways to sync that shared folder across the internet. You can use Synology Drive ShareSync, you can use rsync, or you can use other file sync tools if you prefer. Any of these will keep the shared folder identical on both NAS so that changes made in one location appear in the other.
Inside Synology Photos you then choose the targets you want it to use. Personal backups go to each user’s private photo folder on their own NAS, and anything that is meant for everyone goes into the shared folder. Photos will index both locations so all users can browse the shared library while still keeping their own private space separate.
Synology gives you several ways to sync that shared folder across the internet. You can use Synology Drive ShareSync, you can use rsync, or you can use other file sync tools if you prefer. Any of these will keep the shared folder identical on both NAS so that changes made in one location appear in the other.
Inside Synology Photos you then choose the targets you want it to use. Personal backups go to each user’s private photo folder on their own NAS, and anything that is meant for everyone goes into the shared folder. Photos will index both locations so all users can browse the shared library while still keeping their own private space separate.

