ZooKeeper
HDP 2.5.6 provides ZooKeeper 3.4.6 and no additional Apache patches.
HDP 2.5.5 provided ZooKeeper 3.4.6 and the following Apache patches:
ZOOKEEPER-2227: stmk four-letter word fails execution at server while reading trace mask argument.
HDP 2.5.3 provided ZooKeeper 3.4.6 and no additional Apache patches.
HDP 2.5.0 provided ZooKeeper 3.4.6 and the following Apache patches:
ZOOKEEPER-706: Large numbers of watches can cause session re-establishment to fail.
ZOOKEEPER-1506: Re-try DNS hostname -> IP resolution if node connection fails.
ZOOKEEPER-1574: Set svn:eol-style property to native.
ZOOKEEPER-1575: Adding .gitattributes to prevent CRLF and LF mismatches for source and text files.
ZOOKEEPER-1576: ZooKeeper cluster - failed to connect to cluster if one of the provided IPs causes java.net.UnknownHostException.
ZOOKEEPER-1791: ZooKeeper package includes unnecessary jars that are part of the package.
ZOOKEEPER-1848: [WINDOWS] Java NIO socket channels does not work with Windows ipv6 on JD.
ZOOKEEPER-1876: Add support for installing windows services in .cmd scripts.
ZOOKEEPER-1888: ZkCli.cmd commands fail with "'java' is not recognized as an internal or external command".
ZOOKEEPER-1897: ZK Shell/Cli not processing commands.
ZOOKEEPER-1926: Unit tests should only use build/test/data for data.
ZOOKEEPER-1952: Default log directory and file name can be changed.
ZOOKEEPER-2053: ZooKeeper scripts should honor ZOOKEEPER_HOME
ZOOKEEPER-2064: Prevent resource leak in various classes.