Peer-to-peer setup

One database is great, but it quickly becomes useless if hamsters eat its disks or a tsunami floods its fans. Humanity has been adding redundancy to its setups ever since poligamy was a thing.

DefraDB uses peer-to-peer (P2P) networking for data exchange, synchronization, and replication of documents and commits. P2P communication does not require a central authority. There's two types of peer-to-peer relationships:

• Publisher-Subscriber - Nodes broadcast received updates on a selected collection to listening peers. The state of the collection is shared across peers.
• Replicator - One node unilaterally pushes updates on a specific collection to a target peer.

Setup

When a node is started for the first time, a key pair is generated and stored in its root directory (~/.defradb/ by default). Each node has a unique PeerID generated from its public key. This ID allows other nodes to connect to it.

The following P2P pages assume that you have two instances of DefraDB running on the same network. One way to start multiple DefraDB nodes, each with its root directory and port bindings, is by tweaking the start CLI options.

Start Node1 - Ports 9171 and 9181, root dir ~/.defradb-node1

defradb start --rootdir ~/.defradb-node1 --p2paddr /ip4/127.0.0.1/tcp/9171 --url localhost:9181

Start Node2 - Ports 9172 and 9182, root dir ~/.defradb-node2

defradb start --rootdir ~/.defradb-node2 --p2paddr /ip4/127.0.0.1/tcp/9172 --url localhost:9182

Startup log for Node1

INF cli Starting DefraDB
INF p2p Created LibP2P host PeerID=12D3KooWDy7z9Y6qANCUXADpwYn7cnHoHBAL4MrAuYeWpwA9UePt Address=[/ip4/127.0.0.1/tcp/9171]
...

Startup log for Node2

INF cli Starting DefraDB
INF p2p Created LibP2P host PeerID=12D3KooWHwpvkxhfFtX7kPZSj9XJ5wvgitqZ5mt2uWVpV5kkzQX4 Address=[/ip4/127.0.0.1/tcp/9172]
...