Clone this repo:
  1. 114de13 Call exceptionHandler if Bookie.start fails with exception. by Charan Reddy Guttapalem · 4 days ago master
  2. 14c9979 Add documentation for ByteBuffer lifecycle when adding entries by karanmehta93 · 5 days ago
  3. 2f996dc Enhance deferLedgerLockReleaseOfFailedLedger in ReplicationWorker by Charan Reddy Guttapalem · 12 days ago
  4. 1e63d3c Avoid throwing exception when doing EntryLogger.internalReadEntry by Matteo Merli · 13 days ago
  5. 6acb63f Update bc tests to include versions up to 4.9.x by Enrico Olivelli · 13 days ago

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Apache BookKeeper

Apache BookKeeper is a scalable, fault tolerant and low latency storage service optimized for append-only workloads.

It is suitable for being used in following scenarios:

  • WAL (Write-Ahead-Logging), e.g. HDFS NameNode.
  • Message Store, e.g. Apache Pulsar.
  • Offset/Cursor Store, e.g. Apache Pulsar.
  • Object/Blob Store, e.g. storing state machine snapshots.

Get Started

  • Concepts: Start with the basic concepts of Apache BookKeeper. This will help you to fully understand the other parts of the documentation.
  • Getting Started to setup BookKeeper to write logs.



You can also read Turning Ledgers into Logs to learn how to turn ledgers into continuous log streams. If you are looking for a high level log stream API, you can checkout DistributedLog.



Get In Touch

Report a Bug

For filing bugs, suggesting improvements, or requesting new features, help us out by opening a Github issue or opening an Apache jira.

Need Help?

Subscribe or mail the list - Ask questions, find answers, and also help other users.

Subscribe or mail the list - Join development discussions, propose new ideas and connect with contributors.

Join us on Slack - This is the most immediate way to connect with Apache BookKeeper committers and contributors.


We feel that a welcoming open community is important and welcome contributions.

Contributing Code

  1. See Developer Setup to get your local environment setup.

  2. Take a look at our open issues: JIRA Issues Github Issues.

  3. Review our coding style and follow our pull requests to learn about our conventions.

  4. Make your changes according to our contribution guide.

Improving Website and Documentation

  1. See Building the website and documentation on how to build the website and documentation.