ZooKeeper 3.0.0 Release Notes

You should only have to read this section if you are upgrading from a previous version of ZooKeeper to version 3.0.0, otw skip down to changes

A small number of changes in this release have resulted in non-backward compatible Zookeeper client user code and server instance data. The following instructions provide details on how to migrate code and date from version 2.2.1 to version 3.0.0.

Note: ZooKeeper increments the major version number (major.minor.fix) when backward incompatible changes are made to the source base. As part of the migration from SourceForge we changed the package structure (com.yahoo.zookeeper.* to org.apache.zookeeper.*) and felt it was a good time to incorporate some changes that we had been withholding. As a result the following will be required when migrating from 2.2.1 to 3.0.0 version of ZooKeeper.

• Migrating Client Code

• Migrating Server Data

Migrating Client Code

Java API

1. The java package structure has changed from com.yahoo.zookeeper* to org.apache.zookeeper*. This will probably effect all of your java code which makes use of ZooKeeper APIs (typically import statements)

2. A number of constants used in the client ZooKeeper API were re-specified using enums (rather than ints). See ZOOKEEPER-7, ZOOKEEPER-132 and ZOOKEEPER-139 for full details

3. ZOOKEEPER-18 removed KeeperStateChanged, use KeeperStateDisconnected instead

Also see the current java API

C API

1. A number of constants used in the client ZooKeeper API were renamed in order to reduce namespace collision, see ZOOKEEPER-6 for full details

Migrating Server Data

The following issues resulted in changes to the on-disk data format (the snapshot and transaction log files contained within the ZK data directory) and require a migration utility to be run.

• ZOOKEEPER-27 Unique DB identifiers for servers and clients

• ZOOKEEPER-32 CRCs for ZooKeeper data

• ZOOKEEPER-33 Better ACL management

• ZOOKEEPER-38 headers (version+) in log/snap files

The following must be run once, and only once, when upgrading the ZooKeeper server instances to version 3.0.0.

1. TBD

Version 2.2.1 code, documentation, binaries, etc... are still accessible on SourceForge