CoreOS announced the availability of etcd 2.0, the first stable version of the open source distributed key-value store.
etcd is a popular open source key-value store used in microservices deployments for service discovery, shared configuration and scheduling. The tool is written in Go language and uses the Raft consensus algorithm to manage highly-available replicated log. It is a core component of CoreOS and also powers open source projects such as Kubernetes, Cloud Foundry, Mailgun, Apache Mesos and Mesosphere Datacenter OS. Over 500 open source projects hosted on Github uses etcd. Though it is originally built for CoreOS, etcd works on MacOS, Linux and BSD systems.
The last official release of etcd was 0.4.6. Since then, CoreOS team added many features including improvements to internal etcd protocol to avoid accidental misconfiguration, enhanced backup and recovery for easier recovery from a cluster failure, commands to manage nodes in a cluster and official IANA assigned ports for etcd to listen on TCP 2379 and 2380. Over 150 developers contributed to this release.
This release of etcd includes an improved Raft consensus implementation. Raft is a protocol used in cluster management to maintain identical logs of state changing commands. One node of a cluster is identified as the master which will coordinate with other nodes to agree on the order in which state changes are applied. This protocol forms the core of etcd. The current release of etcd includes more rigorous and faster running tests of the underlying Raft implementation, covering all state machine and cases explained in the original Raft white paper in 1.5 seconds.
Onsi Fakhouri, engineering manager at Pivotal said that strong support for Go language and HTTP API made them choose etcd as the key-value store for Cloud Foundry.
For more details on etcd 2.0, watch the below video by Brandon Philips, CTO at CoreOS.
