etcd – Distributed Key-Value Store

etcd is a distributed, reliable key-value store for the most critical data of a distributed system. It serves as the backbone for Kubernetes and other cloud-native systems.

Key Features

• Consistency: Raft consensus algorithm
• Watch API: Subscribe to key changes
• Transactions: Atomic operations
• TTL: Key expiration support
• gRPC API: Modern communication protocol

Installation

Install etcd on Ubuntu:

ETCD_VER=v3.5.11
curl -L https://github.com/etcd-io/etcd/releases/download/${ETCD_VER}/etcd-${ETCD_VER}-linux-amd64.tar.gz -o etcd.tar.gz
tar xzvf etcd.tar.gz
sudo mv etcd-${ETCD_VER}-linux-amd64/etcd* /usr/local/bin/

Usage Examples

etcd operations:

# Start etcd
etcd --data-dir=/var/lib/etcd

# Put key-value
etcdctl put mykey "Hello World"

# Get value
etcdctl get mykey

# Watch for changes
etcdctl watch mykey

# List all keys
etcdctl get "" --prefix --keys-only

# Delete key
etcdctl del mykey

Benefits

etcd provides reliable storage for distributed system configuration. Its strong consistency guarantees make it ideal for leader election and service discovery.

Download etcd