Ernesto Garbarino
Distributed Application Coordination
A Distributed Application Coordination solution allows distributed applicatons to off-load complex problems such as leader election and slave instance promotion to a central component. The foundation of most of these systems is a distributed, highly-consistent key/value store.
Consul: Consul is a key/value store, health checking & service discovery solution with service mesh (e.g. service-to-service encryption) capabilities. HashiCorps markets it as a batteries-included (e.g. Service Discovery) and easier-to-use alternative to Zookeeper.
Etcd: Etcd is a distributed, consistent key value store that, like most solutions in its category, gracefully handles leader elections during network partitions and will tolerate machine failure, including the leader. Its flagship users are Kubernetes and CloudFoundry.
ZooKeeper: ZooKeeper is a centralised 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.