README version 0.4.5

A highly-available key value store for shared configuration and service discovery. etcd is inspired by Apache ZooKeeper and doozer, with a focus on being:

• Simple: curl'able user facing API (HTTP+JSON)
• Secure: optional SSL client cert authentication
• Fast: benchmarked 1000s of writes/s per instance
• Reliable: properly distributed using Raft

etcd is written in Go and uses the Raft consensus algorithm to manage a highly-available replicated log.

See etcdctl for a simple command line client. Or feel free to just use curl, as in the examples below.

If you're considering etcd for production use, please see: production-ready.md

The latest release and setup instructions are available at GitHub.

You can build etcd from source:

git clone https://github.com/coreos/etcd
cd etcd
./build

This will generate a binary called ./bin/etcd.

NOTE: you need go 1.2+. Please check your installation with

go version

See the development tools documentation for alternative build methods like using Vagrant.

First start a single-machine cluster of etcd:

./bin/etcd

This will bring up etcd listening on port 4001 for client communication and on port 7001 for server-to-server communication.

Next, let's set a single key, and then retrieve it:

curl -L https://127.0.0.1:4001/v2/keys/mykey -XPUT -d value="this is awesome"
curl -L https://127.0.0.1:4001/v2/keys/mykey

You have successfully started an etcd on a single machine and written a key to the store. Now it's time to dig into the full etcd API and other guides.

• Explore the full API.
• Set up a multi-machine cluster.
• Learn the config format, env variables and flags.
• Find language bindings and tools.
• Learn about the dashboard, lock and leader election modules.
• Use TLS to secure an etcd cluster.
• Tune etcd.
• Upgrade from old version.

• Mailing list: etcd-dev
• IRC: #coreos on freenode.org
• Planning/Roadmap: milestones
• Bugs: issues

See CONTRIBUTING for details on submitting patches and the contribution workflow.

etcd uses semantic versioning New minor versions may add additional features to the API.

You can get the version of etcd by issuing a request to /version:

curl -L https://127.0.0.1:4001/version

Clients are encouraged to use the v2 API. The v1 API will not change.

The v2 API responses should not change after the 0.2.0 release but new features will be added over time.

During the pre-v1.0.0 series of releases we may break the API as we fix bugs and get feedback.

etcd has known issues on 32bit systems. We plan to address these issues after the 0.4 release.

etcd is under the Apache 2.0 license. See the LICENSE file for details.