Open-source alternatives to Libnetwork

etcd is a distributed key-value store and configuration store designed to maintain a consistent set of data across a cluster of nodes. It functions as a reliable registry for storing and synchronizing critical settings and metadata used by distributed applications. The system implements the Raft consensus algorithm to ensure data consistency and leader election across servers. To protect data transfers and verify node identities, it utilizes a network security layer based on mutual TLS and client certificates. Its capabilities cover distributed configuration management, cluster state synchro

Flannel is a virtual networking layer and Kubernetes CNI plugin that provides automated subnet management and Layer 3 overlay connectivity. It functions as a container network fabric, enabling distributed containers and pods across multiple hosts to communicate using unique IP addresses without manual routing configuration. The system operates as a distributed subnet manager, allocating and persisting unique subnet ranges to hosts using a distributed key-value store. This ensures conflict-free container addressing across the cluster by tracking subnet leases and persisting network metadata.

Service discovery via DNS for docker