New Features and improvements of hadoop 2.5.0

Apache hadoop 2.5.0 is a small version on the 2.x. y release line. It is built on the stable version 2.4.1. Main features and improvements:

1. Common

A) Improved Authentication when using the HTTP proxy server. This is useful when using webhdfs through a proxy server.

B) added a new hadoop metric monitoring sink that allows direct writing to graphite.

C) specifications related to hadoop file system compatibility.

2. HDFS

A) supports POSIX-style extended file systems. For more details, see extended attributes in HDFS documentation.

B) supports offline Image Browsing. The client can now browse a fsimage through the webhdfs API.

C) the NFS gateway has received a lot of support improvements and bug fixes. The hadoop Portmapper does not need to run the gateway. The Gateway can now reject connections from ports without permissions.

D) The web UI of secondarynamenode, journalnode, and datanode has been beautified using HTML5 and Js.

3. Yarn

A) The rest API of yarn currently supports write/modify operations. You can use rest APIs to submit and kill applications.

B) the timeline is stored in yarn to store common and special information of an application. Kerberos authentication is supported.

C) The fair scheduler supports dynamically layered user queues. During running, user queues are dynamically created in any specified parent queue.