Project status

This project is in alpha stage. It is not ready for production use.

For now only KV interface is supported. And it's not fully tested.

General Architecture

The Etcd Sharding Proxy Serves to clients as an etcd endpoint. It proxies requests to the correct shard etcd cluster based on the key.

                          │
                          │
                          │
                 ┌────────▼────────┐
                 │  Load Balancer  │
                 └────────┬────────┘
                          │
                          │
                          │
             ┌────────────▼────────────┐
             │   Etcd Sharding Proxy   │
             └────────────┬────────────┘
                          │
                          │
        ┌─────────────────┼─────────────────┐
        │                 │                 │
┌───────▼───────┐ ┌───────▼───────┐ ┌───────▼───────┐
│               │ │               │ │               │
│  Etcd Cluster │ │  Etcd Cluster │ │  Etcd Cluster │
│               │ │               │ │               │
└───────────────┘ └───────────────┘ └───────────────┘

Compatibility

Revision, MemberId, ClusterId of each shard is used. Hence:

• Field revision in Range / RangeDelete requests across different shards will not work.
• Txn cannot be executed across multiple shards. NOTE: The proxy will not do check for this. If you use Txn across multiple shards, the result is undefined.
• Compact is not supported

Quick Start with Docker

Start 3 etcd and the proxy:

# start backend etcd
docker run --name etcd-0 -d --rm -p 12379:2379 gcr.io/etcd-development/etcd:v3.5.7 etcd --listen-client-urls http://0.0.0.0:2379 -advertise-client-urls=http://0.0.0.0:2379
docker run --name etcd-1 -d --rm -p 22379:2379 gcr.io/etcd-development/etcd:v3.5.7 etcd --listen-client-urls http://0.0.0.0:2379 -advertise-client-urls=http://0.0.0.0:2379
docker run --name etcd-2 -d --rm -p 32379:2379 gcr.io/etcd-development/etcd:v3.5.7 etcd --listen-client-urls http://0.0.0.0:2379 -advertise-client-urls=http://0.0.0.0:2379

# start proxy
go run ./cmd/proxy -config ./examples/config.yaml

Run cmds (need etcdctl installed):

# try the features
etcdctl put a 1
etcdctl put b 2
etcdctl put c 3
etcdctl get "" --from-key
etcdctl del "" --from-key
etcdctl get "" --from-key