7077 Apache-Spark TCP
Reference for TCP port 7077, commonly associated with Apache-Spark.
What it's for
Port 7077 is the default port for the Apache Spark standalone cluster manager's master node — the process that coordinates distributed data-processing jobs across worker nodes in a Spark cluster. Client applications submitting Spark jobs connect to this port to have their work distributed and executed across the cluster's available workers.
Protocol basics
Communication with the Spark master runs over TCP using Spark's own internal RPC protocol, coordinating job scheduling, resource allocation, and worker registration across the cluster. This is distinct from Spark's separate web UI (typically port 8080 in a standalone deployment) used purely for monitoring job progress and cluster status. Like other cluster-coordination ports, 7077 should be restricted to trusted infrastructure — the client applications and worker nodes that are actually part of the Spark deployment — rather than exposed broadly.