A three-node cluster
The yggr-examples crate ships a replicated KV service. To see it running:
./yggr-examples/run-three-node.sh
That brings up three kv processes on localhost, has them elect a leader, and exposes a text protocol you can drive with nc.
What the script does
Each node starts with:
#![allow(unused)]
fn main() {
let config = Config::new(my_node_id, peer_ids);
let storage = DiskStorage::open(&data_dir).await?;
let transport = TcpTransport::start(my_node_id, listen_addr, peer_addrs).await?;
let node = Node::start(config, MyStateMachine::default(), storage, transport).await?;
}The leader accepts write(cmd) from clients. Followers return NotLeader with a hint so the client can retry against the right node.