[haadcode]

It's true that availability is not "automatic" as per the software itself (rarely is in P2P networks). To make sure the data stays online (whether IPFS or OrbitDB), one needs to make sure there are enough nodes serving the data. In OrbitDB the replication protocol will make sure the full database is downloaded and served upon opening the database and as all db-data is IPFS-data, the db will be served just like any content on IPFS. So for example, for an application built with OrbitDB and IPFS, one would probably want to run some nodes themselves to "pin" (IPFS parlance) the databases and serve them to the network.

Edit: There's an open issue for a "OrbitDB pinning service" (https://github.com/orbitdb/orbit-db/issues/352), it's in the works atm.

[realPubkey]

But doesnt this mean I just distribute a big json over ipfs? Where do I need orbitDB for that?

[haadcode]

Not quite. The data structures for the "database" part are more complex than a single json structure. Each update to the database is an "individual json" which get linked together using an append-only log CRDT (https://github.com/orbitdb/ipfs-log) and you'd essentially serve that log. So instead of "one big json", it's "many small jsons" and the state (view) of the database gets calculated from those small jsons.

[realPubkey]

Thank for clearing that. I think I have to read the docs more carefully