Скачать или смотреть System Design : How Leader Election Works (Includes Java Code)

System Design : How Leader Election Works (Includes Java Code)

Technical deep-dive into leader election in distributed systems, ZooKeeper internals, and how HDFS uses it to manage active NameNode in HA setups using Java sample code.

This video is a deep-dive into leader election in distributed systems, focusing on the critical properties that make or break real-world implementations: uniqueness, liveness, fairness, and fault tolerance.

We explore how Apache ZooKeeper is used in production systems to enforce these guarantees—specifically through ephemeral znodes, sequential znodes, and watches—without getting lost in unnecessary theory.

The discussion then shifts to HDFS (Hadoop Distributed File System) and its HA architecture, where ZooKeeper ensures a single active NameNode across the cluster. The second half walks through the actual Java code that mirrors how HDFS integrates with ZooKeeper, showcasing how leader election logic plays out in practice.

This isn’t a surface-level overview. It's a grounded technical analysis aimed at engineers working with or designing resilient distributed systems.

Topics Covered:
Leader election in distributed systems
Why it matters
ZooKeeper basics
HDFS active NameNode election via ZooKeeper
Java implementation details


Hashtags:
#systemdesign #interviewquestions #hdfs #zookeeper #leaderelection #distributedsystems #java#softwaredeveloper #softwareengineer #softwarearchitecture #realworldsystem #systeminternals #seniorengineer