Apache ZooKeeper 3.5.3-beta Has Been Released

Categories: ZooKeeper

The Apache ZooKeeper team has announced that Apache ZooKeeper release 3.5.3-beta is now available! This release is the first beta release of the 3.5 series, which cover 77 issues, thirteen of which were considered blockers. Here are some highlights:

New Feature

  • ZOOKEEPER-2719 Enable creation of TTL nodes, which are znode that’s not tied to a session and will get cleaned up automatically once expired.

Security Fixes

  • ZOOKEEPER-2014 Only admin roles should be allowed to reconfigure a cluster
  • ZOOKEEPER-2693 Prevent DOS attack on wchp/wchc four letter words (4lw)

Critical Bug Fixes

  • ZOOKEEPER-2383 Solve startup race in ZooKeeperServer
  • ZOOKEEPER-2172 Cluster crashes when reconfig a new node as a participant
  • ZOOKEEPER-2737 NettyServerCnxFactory leaks connection if exception happens while writing to a channel
  • ZOOKEEPER-2247 Zookeeper service becomes unavailable when leader fails to write transaction log
  • ZOOKEEPER-2080 Fix deadlock in dynamic reconfiguration
  • ZOOKEEPER-2687 Deadlock while shutting down the Leader server

Stability, Compatibility and Testing

The 3.5 series has been through three alpha releases already, incorporating feedback from users and addressing found issues. The Apache community is now considering the 3.5.3 release to be of beta quality.  It is important to note that 3.5.3 is not yet ready for production. It is an early release that users can start testing so that we can stabilize later 3.5.x release towards the stable 3.5 release, which we will adopt into a future CDH release.

Getting Involved

The Apache ZooKeeper project is working on a number of new features. Our How To Contribute page is a great place to start if you’re interested in getting involved as a developer, or dive right into an open issue.


A special thanks to everyone who contributed to the release (reporting issues, fixing bugs, reviewing changes, writing documentation, etc), especially Patrick Hunt, Flavio Junqueira, Rakesh Radhakrishnan, Mohammad Arshad, Sandeep Shrids, and Arvind Kandhare who helped verification and voting of the release candidates!

About Authors:

Michael Han is a Software Engineer at Cloudera, committer of Apache ZooKeeper project, and the release manager of Apache ZooKeeper 3.5.3-beta release.


2 responses on “Apache ZooKeeper 3.5.3-beta Has Been Released

  1. L.J.W

    When will 3.5 version go to final?We expect for local session feature.and wait for very long time.