etcd vs Zookeeper: What are the differences?
Developers describe etcd as "A distributed consistent key-value store for shared configuration and service discovery". etcd is a distributed key value store that provides a reliable way to store data across a cluster of machines. It’s open-source and available on GitHub. etcd gracefully handles master elections during network partitions and will tolerate machine failure, including the master. On the other hand, Zookeeper is detailed as "Because coordinating distributed systems is a Zoo". A centralized service for maintaining configuration information, naming, providing distributed synchronization, and providing group services. All of these kinds of services are used in some form or another by distributed applications.
etcd and Zookeeper can be primarily classified as "Open Source Service Discovery" tools.
"Service discovery" is the primary reason why developers consider etcd over the competitors, whereas "High performance ,easy to generate node specific config" was stated as the key factor in picking Zookeeper.
etcd is an open source tool with 25.5K GitHub stars and 5.18K GitHub forks. Here's a link to etcd's open source repository on GitHub.
Shopify, SendGrid, and hike are some of the popular companies that use Zookeeper, whereas etcd is used by CNCFlora, Beam, and Giant Swarm. Zookeeper has a broader approval, being mentioned in 116 company stacks & 48 developers stacks; compared to etcd, which is listed in 27 company stacks and 11 developer stacks.