Possible new user here investigating the service. As I understand it, 2 devices can be synced only if they have each other’s device IDs. How does this work when one wants to sync a folder among 3 or more devices such that syncing continues even if the original device is offline? For example, consider 3 devices: A, B, and C among which a folder \Test is to be synced. Device ID exchanges would proceed as:
However, the problem with the above is B & C are unaware of each other and so if A goes offline B & C cannot sync. This means the Syncthing network graph in this configuration is hub-and-spoke instead of each member being connected to every other one. An obvious solution is to do the Device ID exchange:
However even if that is possible it now presents a scaling problem: as the number of peers grows, so does the number of ID exchanges. Syncing a folder across 5 devices would require a whopping 15 ID exchanges.
Do I have the above right? Is there an easier way or something I’m missing, e.g. on a per folder basis does a peer automatically tell a new peer of pre-existing peers? Or is Syncthing unable to support more than 2 devices per folder?