HashiCorp Nomad: A Lightweight Scheduler for JVM Service Orchestration Compared to Kubernetes

HashiCorp's open-source software, Nomad, consists of a lightweight resource manager and scheduler, making its structure simpler and performance faster than Kubernetes. It supports various drivers beyond Docker and RKT, such as fork/exec, qemu, java, and LXC. Notably, the Java driver enables the orchestration of JVM-based services without containerization. HashiCorp highlights the 'Nomad Million Container Challenge' on its website, showcasing a case where 1 million containers were deployed across 5,000 hosts in 5 minutes using Nomad. When executing services, Nomad assigns random ports and passes them via environment variables, with deployment and rollback proceeding through plan and run steps. Executed services are registered with Consul, and cluster status can be monitored in real-time via the open-source Web UI hashi-ui, in addition to the officially supported Atlas.