Release Notes for MongoDB 2.4

March 19, 2013

MongoDB 2.4 includes enhanced geospatial support, switch to V8 JavaScriptengine, security enhancements, and text search (beta) and hashed index.

Minor Releases

2.4.14 – April 28, 2015

2.4.13 – February 25, 2015

2.4.12 – October 16, 2014

2.4.11 – August 18, 2014

2.4.10 – April 4, 2014

2.4.9 – January 10, 2014

2.4.8 – November 1, 2013

2.4.7 – October 21, 2013

2.4.6 – August 20, 2013

2.4.5 – July 3, 2013

2.4.4 – June 4, 2013

2.4.3 – April 23, 2013

2.4.2 – April 17, 2013

2.4.1 – April 17, 2013

Major New Features

The following changes in MongoDB affect both standard and Enterpriseeditions:

Add support for text search of content in MongoDB databases as abeta feature. See Text Indexes for more information.

Geospatial Support Enhancements

Hashed Index

Add new hashed index to index documentsusing hashes of field values. When used to index a shard key, thehashed index ensures an evenly distributed shard key. See alsoHashed Sharding.

Improvements to the Aggregation Framework

  • Improve support for geospatial queries. See the$geoWithin operator and the $geoNear pipelinestage.
  • Improve sort efficiency when the $sort stage immediatelyprecedes a $limit in the pipeline.
  • Add new operators $millisecond and$concat and modify how $min operator processesnull values.

Changes to Update Operators

Additional Limitations for Map-Reduce and $where Operations

The mapReduce command, group command, andthe $where operator expressions cannot access certainglobal functions or properties, such as db, that are availablein the mongo shell. See the individual command oroperator for details.

Improvements to serverStatus Command

Provide additional metrics and customization for theserverStatus command. See db.serverStatus()and serverStatus for more information.

Security Enhancements

  • Introduce a role-based access control systemUser Privileges now use a newformat for Privilege Documents.
  • Enforce uniqueness of the user in user privilege documents perdatabase. Previous versions of MongoDB did not enforce thisrequirement, and existing databases may have duplicates.
  • Support encrypted connections using SSL certificates signed by aCertificate Authority. See Configure mongod and mongos for TLS/SSL.

For more information on security and risk management strategies, seeMongoDB Security Practices and Procedures.

Performance Improvements

V8 JavaScript Engine

Change default JavaScript engine from SpiderMonkey to V8. The changeprovides improved concurrency for JavaScript operations, modernizedJavaScript implementation, and the removal of non-standardSpiderMonkey features, and affects all JavaScript behavior includingthe commands mapReduce, group, andeval and the query operator $where.

See JavaScript Changes in MongoDB 2.4 for more information aboutall changes .

BSON Document Validation Enabled by Default for mongod and mongorestore

Enable basic BSON object validation for mongodand mongorestore when writing to MongoDB data files. SeewireObjectCheck for details.

Index Build Enhancements

Set Parameters as Command Line Options

Provide —setParameter as a command line option formongos and mongod. See mongod andmongos for list of available options forsetParameter.

Changed Replication Behavior for Chunk Migration

By default, each document move during chunk migration in a sharded cluster propagates toat least one secondary before the balancer proceeds with its nextoperation. See Chunk Migration and Replication.

Improved Chunk Migration Queue Behavior

Increase performance for moving multiple chunks off an overloadedshard. The balancer no longer waits for the current migration’sdelete phase to complete before starting the next chunk migration.See Asynchronous Chunk Migration Cleanup for details.

Enterprise

The following changes are specific to MongoDB Enterprise Editions:

SASL Library Change

In 2.4.4, MongoDB Enterprise uses Cyrus SASL. Earlier 2.4 Enterpriseversions use GNU SASL (libgsasl). To upgrade to 2.4.4 MongoDBEnterprise or greater, you must install all package dependenciesrelated to this change, including the appropriate Cyrus SASL GSSAPIlibrary. See Install MongoDB Enterprise for details ofthe dependencies.

New Modular Authentication System with Support for Kerberos

In 2.4, the MongoDB Enterprise now supports authentication via aKerberos mechanism. SeeConfigure MongoDB with Kerberos Authentication on Linuxfor more information. For drivers that provide support forKerberos authentication to MongoDB, refer to Driver Support.

For more information on security and risk management strategies, seeMongoDB Security Practices and Procedures.

Additional Information

Platform Notes

For macOS, MongoDB 2.4 only supports macOS versions 10.6 (Snow Leopard)and later. There are no other platform support changes in MongoDB2.4. See the downloads page formore information on platform support.

Upgrade Process

See Upgrade MongoDB to 2.4 for full upgrade instructions.

Other Resources