2.6.txt

=============================
Release Notes for MongoDB 2.6
=============================

.. default-domain:: mongodb

.. contents:: On this page
   :local:
   :backlinks: none
   :depth: 1
   :class: twocols

*April 8, 2014*

MongoDB 2.6 is now available. Key features include aggregation
enhancements, text-search integration, query-engine improvements, a new
write-operation protocol, and security enhancements.

Minor Releases
--------------

.. class:: hidden

   .. toctree::

      /release-notes/2.6-changelog

2.6.12 -- Mar 24, 2016
~~~~~~~~~~~~~~~~~~~~~~

- Fixed issue with MMAPv1 journaling where the "last sequence number"
  file (``lsn`` file) may be ahead of what is synced to the data files:
  :issue:`SERVER-22261`.

- Fixed issue that permitted the creation of new role with the same
  name as a :doc:`built-in role </reference/built-in-roles>`:
  :issue:`SERVER-19284`.

- Fixed issue where some index operations running during an active migration 
  may cause the migration operation to skip some documents:
  :issue:`SERVER-22535`.

- `All issues closed in 2.6.12
  <https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.12%22%20AND%20project%20%3D%20SERVER>`_

2.6.11 -- Aug 12, 2015
~~~~~~~~~~~~~~~~~~~~~~

- Improvements to query plan ranking :issue:`SERVER-17815`

- Improved ability for :binary:`~bin.mongos` to detect replica set
  failover and correctly route read operations to the new
  primary :issue:`SERVER-18280`

- Improved reporting of queries in ``getMore`` operation in
  :method:`db.currentOp()` and the database
  profiler :issue:`SERVER-16265`

- `All issues closed in 2.6.11
  <https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.11%22%20AND%20project%20%3D%20SERVER>`_

2.6.10 -- May 19, 2015
~~~~~~~~~~~~~~~~~~~~~~

- Improve user cache invalidation enforcement on :binary:`~bin.mongos`
  :issue:`SERVER-11980`

- Provide correct rollbacks for collection creation
  :issue:`SERVER-18211`

- Allow user inserts into the :data:`system.profile` collection
  :issue:`SERVER-18211`

- Fix to query system to ensure non-negation predicates get chosen
  over negation predicates for multikey index bounds construction
  :issue:`SERVER-18364`

- `All issues closed in 2.6.10
  <https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.10%22%20AND%20project%20%3D%20SERVER>`_

2.6.9 -- March 24, 2015
~~~~~~~~~~~~~~~~~~~~~~~

- Resolve connection handling related crash with :binary:`~bin.mongos`
  instances :issue:`SERVER-17441`

- Add server parameter to configure idle cursor timeout
  :issue:`SERVER-8188`

- Remove duplicated (orphan) documents from aggregation pipelines with
  ``_id`` queries in sharded clusters :issue:`SERVER-17426`

- Fixed crash in :dbcommand:`geoNear` queries with multiple
  ``2dsphere`` indexes :issue:`SERVER-14723`

- `All issues closed in 2.6.9
  <https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.9%22%20AND%20project%20%3D%20SERVER>`_

2.6.8 -- February 25, 2015
~~~~~~~~~~~~~~~~~~~~~~~~~~

- Add :dbcommand:`listCollections` command functionality to 2.6 shell
  and client :issue:`SERVER-17087`

- :dbcommand:`copydb`/\ :dbcommand:`clone` commands can crash the
  server if a primary steps down :issue:`SERVER-16599`

- Secondary fasserts trying to replicate an index
  :issue:`SERVER-16274`

- Query optimizer should always use equality predicate over unique
  index when possible :issue:`SERVER-15802`

- `All issues closed in 2.6.8
  <https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.8%22%20AND%20project%20%3D%20SERVER>`_

2.6.7 -- January 13, 2015
~~~~~~~~~~~~~~~~~~~~~~~~~~

- Decreased :binary:`~bin.mongos` memory footprint when shards have several
  tags :issue:`SERVER-16683`

- Removed check for shard version if the primary server is down
  :issue:`SERVER-16237`

- Fixed: ``/etc/init.d/mongod`` startup script failure with dirname message
  :issue:`SERVER-16081`

- Fixed: :binary:`~bin.mongos` can cause shards to hit the in-memory sort limit
  by requesting more results than needed :issue:`SERVER-14306`

- `All issues closed in 2.6.7
  <https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.7%22%20AND%20project%20%3D%20SERVER>`_

2.6.6 -- December 09, 2014
~~~~~~~~~~~~~~~~~~~~~~~~~~

- Fixed: Evaluating candidate query plans with concurrent writes on same
  collection may crash :binary:`~bin.mongod` :issue:`SERVER-15580`

- Fixed: 2.6 :binary:`~bin.mongod` crashes with segfault when added to a 2.8 replica set
  with 12 or more members :issue:`SERVER-16107`

- Fixed: :query:`$regex`, :query:`$in` and :query:`$sort` with index returns too
  many results :issue:`SERVER-15696`

- Change: :dbcommand:`moveChunk` will fail if there is data on the target
  shard and a required index does not exist.
  :issue:`SERVER-12472`

- Primary should abort if encountered problems writing to the oplog
  :issue:`SERVER-12058`

- `All issues closed in 2.6.6 <https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.6%22%20AND%20project%20%3D%20SERVER>`_


2.6.5 -- October 07, 2014
~~~~~~~~~~~~~~~~~~~~~~~~~

- :query:`$rename` now uses correct dotted source paths :issue:`SERVER-15029`

- Partially written journal last section does not affect recovery
  :issue:`SERVER-15111`

- Explicitly zero ``.ns`` files on creation :issue:`SERVER-15369`

- Plan ranker will no longer favor intersection plans if predicate generates empty range
  index scan :issue:`SERVER-14961`

- Generate Community and Enterprise packages for SUSE 11
  :issue:`SERVER-10642`

- `All issues closed in 2.6.5 <https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.5%22%20AND%20project%20%3D%20SERVER>`_

2.6.4 -- August 11, 2014
~~~~~~~~~~~~~~~~~~~~~~~~

- Fix for ``text`` index where under specific circumstances, in-place
  updates to a ``text``-indexed field may result in
  incorrect/incomplete results :issue:`SERVER-14738`

- Check the size of the split point before performing a manual split
  chunk operation :issue:`SERVER-14431`

- Ensure read preferences are re-evaluated by drawing secondary
  connections from a global pool and releasing back to the pool at the
  end of a query/command :issue:`SERVER-9788`

- Allow read from secondaries when both audit and authorization are
  enabled in a sharded cluster :issue:`SERVER-14170`

- `All issues closed in 2.6.4 <https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.4%22%20AND%20project%20%3D%20SERVER>`_

2.6.3 -- June 19, 2014
~~~~~~~~~~~~~~~~~~~~~~

- Equality queries on ``_id`` with projection may return no results
  on sharded collections :issue:`SERVER-14302`.

- Equality queries on ``_id`` with projection on ``_id`` may return
  orphan documents on sharded collections :issue:`SERVER-14304`.

- `All issues closed in 2.6.3 <https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.3%22%20AND%20project%20%3D%20SERVER>`_.


2.6.2 -- June 16, 2014
~~~~~~~~~~~~~~~~~~~~~~

- Query plans with differing performance can tie during plan ranking
  :issue:`SERVER-13675`.

- :binary:`~bin.mongod` may terminate if x.509 authentication certificate is invalid
  :issue:`SERVER-13753`.

- Temporary map/reduce collections are incorrectly replicated to secondaries
  :issue:`SERVER-13981`.

- :binary:`~bin.mongos` incorrectly targets multiple shards for nested
  field shard key predicates :issue:`SERVER-14138`.

- :method:`rs.stepDown()` during mapReduce causes ``fassert`` when
  writing to op log :issue:`SERVER-14186`.

..
   - :ref:`2.6.2 Changelog <2.6.2-changelog>`.

- `All issues closed in 2.6.2 <https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.2%22%20AND%20project%20%3D%20SERVER>`_.

2.6.1 -- May 5, 2014
~~~~~~~~~~~~~~~~~~~~

- Fix to install MongoDB service on Windows with the ``--install``
  option :issue:`SERVER-13515`.

- Allow direct upgrade from 2.4.x to 2.6.0 via ``yum``
  :issue:`SERVER-13563`.

- Fix issues with background index builds on secondaries:
  :issue:`SERVER-13589` and :issue:`SERVER-13620`.

- Redact credential information passed as startup options
  :issue:`SERVER-13644`.

- :ref:`2.6.1 Changelog <2.6.1-changelog>`.

- `All issues closed in 2.6.1 <https://jira.mongodb.org/issues/?jql=fixVersion%20%3D%20%222.6.1%22%20AND%20project%20%3D%20SERVER>`_.

Major Changes
-------------

The following changes in MongoDB affect both the standard and Enterprise
editions:

.. _rn-2.6-aggregation-cursor:

Aggregation Enhancements
~~~~~~~~~~~~~~~~~~~~~~~~

The aggregation pipeline adds the ability to return result sets of any
size, either by returning a cursor or writing the output to
a collection. Additionally, the aggregation pipeline supports
variables and adds new operations to handle sets and redact data.

- The :method:`db.collection.aggregate()` now returns a cursor, which
  enables the aggregation pipeline to return result sets of any size.

- Aggregation pipelines now support an ``explain`` operation to aid
  analysis of aggregation operations.

- Aggregation can now use a more efficient external-disk-based sorting
  process.

- New pipeline stages:

  - :pipeline:`$out` stage to output to a collection.

  - :pipeline:`$redact` stage to allow additional control to accessing
    the data.

- New or modified operators:

  - :doc:`set expression operators
    </reference/operator/aggregation-set>`.

  - :expression:`$let` and :expression:`$map` operators to allow for
    the use of variables.

  - :expression:`$literal` operator and :expression:`$size` operator.

  - :expression:`$cond` expression now accepts either an object or
    an array.

.. _rel-notes-text-query-operator:

Text Search Integration
~~~~~~~~~~~~~~~~~~~~~~~

Text search is now enabled by default, and the query system, including
the aggregation pipeline :pipeline:`$match` stage, includes the
:query:`$text` operator, which resolves text-search queries.

MongoDB 2.6 includes an updated :doc:`text index
</core/index-text>` format and deprecates the :dbcommand:`text`
command.

.. _rel-notes-data-modification:

Insert and Update Improvements
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Improvements to the update and insert systems include additional
operations and improvements that increase consistency of modified
data.

- .. include:: /includes/fact-update-field-order.rst
     :start-after: order-of-document-fields
     :end-before: .. versionchanged

- New or enhanced update operators:

  - :update:`$bit` operator supports bitwise ``xor`` operation.

  - :update:`$min` and :update:`$max` operators that perform
    conditional update depending on the relative size of the specified
    value and the current value of a field.

  - :update:`$push` operator has enhanced support for the
    :update:`$sort`, :update:`$slice`, and :update:`$each` modifiers
    and supports a new :update:`$position` modifier.

  - :update:`$currentDate` operator to set the value of a field to the
    current date.

- The :update:`$mul` operator for multiplicative increments for insert
  and update operations.

.. seealso:: :ref:`update-operations-incompatibility`

.. _rel-notes-write-operations:

New Write Operation Protocol
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

A new write protocol integrates write operations with
write concerns. The protocol also provides improved
support for bulk operations.

MongoDB 2.6 adds the write commands :dbcommand:`insert`,
:dbcommand:`update`, and :dbcommand:`delete`, which provide the basis
for the improved bulk insert. All officially supported MongoDB drivers
support the new write commands.

The :binary:`~bin.mongo` shell now includes
methods to perform bulk-write operations. See :method:`Bulk()` for
more information.

.. seealso:: :ref:`write-methods-incompatibility`

MSI Package for MongoDB Available for Windows
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

MongoDB now distributes MSI packages for Microsoft Windows. This is the
recommended method for MongoDB installation under Windows.

.. _2.6-relnotes-security:

Security Improvements
---------------------

MongoDB 2.6 enhances support for secure deployments through improved SSL
support, x.509-based authentication, an improved authorization system
with more granular controls, as well as centralized credential storage, and
improved user management tools.

Specifically these changes include:

- A new :ref:`authorization model <authorization>` that provides the
  ability to create custom :ref:`user-defined-roles` and the ability to
  specify user privileges at a collection-level granularity.

- Global user management, which stores all user and
  user-defined role data in the ``admin`` database and provides a new
  set of commands for managing users and roles.

- x.509 certificate authentication for :doc:`client authentication
  </tutorial/configure-x509-client-authentication>` as well as for
  :doc:`internal authentication
  </tutorial/configure-x509-member-authentication>` of sharded cluster and/or
  replica set  members. x.509 authentication is only available
  for deployments using SSL.

- Enhanced SSL Support:

  - :doc:`Rolling upgrades of clusters
    </tutorial/upgrade-cluster-to-ssl>` to use SSL.

  - :ref:`mongodb-tools-support-ssl` support connections to
    :binary:`~bin.mongod` and :binary:`~bin.mongos` instances using SSL
    connections.

  - :ref:`Prompt for passphrase <ssl-certificate-password>`
    by :binary:`~bin.mongod` or :binary:`~bin.mongos` at startup.

  - Require the use of strong SSL ciphers, with a minimum 128-bit key
    length for all connections. The strong-cipher requirement prevents
    an old or malicious client from forcing use of a weak cipher.

- MongoDB disables the http interface by default, limiting
  :doc:`network exposure </core/security-network>`. To enable the
  interface, see :setting:`~net.http.enabled`.

.. seealso:: :ref:`authentication-incompatibility`,
   :ref:`ssl-hostname-validation`,
   and :doc:`/administration/security-checklist`.

Query Engine Improvements
-------------------------

- MongoDB can now use :doc:`index intersection
  </core/index-intersection>` to fulfill queries supported by more
  than one index.

- :ref:`index-filters` to limit which indexes can become the winning
  plan for a query.

- :doc:`/reference/method/js-plan-cache` methods to view and clear the
  :doc:`query plans </core/query-plans>` cached by the query optimizer.

- MongoDB can now use :method:`~cursor.count()` with
  :method:`~cursor.hint()`. See :method:`~cursor.count()` for details.

Improvements
------------

Geospatial Enhancements
~~~~~~~~~~~~~~~~~~~~~~~

- :ref:`2dsphere indexes version 2
  <2dsphere-v2>`.

- Support for :ref:`geojson-multipoint`,
  :ref:`geojson-multilinestring`, :ref:`geojson-multipolygon`, and
  :ref:`geojson-geometrycollection`.

- Support for geospatial query clauses in :query:`$or` expressions.

.. seealso::
   :ref:`2.6-2dsphere-version-incompatibility`,
   :ref:`2.6-geo-maxDistance-incompatibility`,
   :ref:`2.6-uniqueDocs-incompatibility`,
   :ref:`2.6-geospatial-validation-incompatibility`

Index Build Enhancements
~~~~~~~~~~~~~~~~~~~~~~~~

- :ref:`Background index build
  <index-creation-background>` allowed on
  secondaries. If you initiate a background index build on a
  :term:`primary`, the secondaries will replicate the index build in
  the background.

- Automatic rebuild of interrupted index builds after a restart.

  - If a standalone or a primary instance terminates during an index
    build *without a clean shutdown*, :binary:`~bin.mongod` now restarts
    the index build when the instance restarts. If the instance shuts
    down cleanly or if a user kills the index build, the interrupted
    index builds do not automatically restart upon the restart of the
    server.

  - If a secondary instance terminates during an index build, the
    :binary:`~bin.mongod` instance will now restart the interrupted index
    build when the instance restarts.

  To disable this behavior, use the :option:`--noIndexBuildRetry <mongod --noIndexBuildRetry>`
  command-line option.

- :method:`~db.collection.ensureIndex()` now wraps a new
  :dbcommand:`createIndex` command.

- The ``dropDups`` option to :method:`~db.collection.ensureIndex()`
  and :dbcommand:`createIndex` is deprecated.

.. seealso:: :ref:`2.6-index-key-length-incompatibility`

Enhanced Sharding and Replication Administration
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

- New :dbcommand:`cleanupOrphaned` command to remove :term:`orphaned
  documents <orphaned document>` from a shard.

- New :dbcommand:`mergeChunks` command to combine contiguous chunks
  located on a single shard. See :dbcommand:`mergeChunks` and
  :doc:`/tutorial/merge-chunks-in-sharded-cluster`.

- New :method:`rs.printReplicationInfo()` and
  :method:`rs.printSlaveReplicationInfo()` methods to provide a
  formatted report of the status of a replica set from the perspective
  of the primary and the secondary, respectively.

Configuration Options YAML File Format
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

MongoDB 2.6 supports a YAML-based configuration file format in addition
to the previous configuration file format. See the documentation of
the :doc:`Configuration File </reference/configuration-options>` for
more information.

Operational Changes
-------------------

Storage
~~~~~~~

:collflag:`usePowerOf2Sizes` is now the default allocation strategy for
all new collections. The new allocation strategy uses more storage
relative to total document size but results in lower levels of
storage fragmentation and more predictable storage capacity planning
over time.

To use the previous *exact-fit allocation strategy*:

- For a specific collection, use :dbcommand:`collMod` with
  :collflag:`usePowerOf2Sizes` set to ``false``.

- For all new collections on an entire :binary:`~bin.mongod` instance,
  set :parameter:`newCollectionsUsePowerOf2Sizes` to ``false``.

  .. include:: /includes/fact-definition-new-collection.rst

See :v2.6:`/core/storage` for more information about MongoDB's storage system.

Networking
~~~~~~~~~~

- Removed upward limit for the :setting:`~net.maxIncomingConnections` for :binary:`~bin.mongod`
  and :binary:`~bin.mongos`. Previous versions capped the maximum possible
  :setting:`~net.maxIncomingConnections` setting at ``20,000`` connections.

- Connection pools for a :binary:`~bin.mongos` instance may be used by multiple
  MongoDB servers. This can reduce the number of connections needed
  for high-volume workloads and reduce resource consumption in
  sharded clusters.

- The C++ driver now monitors :term:`replica set` health with the
  :dbcommand:`isMaster` command instead of
  :dbcommand:`replSetGetStatus`. This allows the C++ driver to support
  systems that require authentication.

- New :method:`cursor.maxTimeMS()` and corresponding ``maxTimeMS``
  option for commands to specify a time limit.

Tool Improvements
~~~~~~~~~~~~~~~~~

- :binary:`~bin.mongo` shell supports a global :ref:`/etc/mongorc.js
  <mongo-global-mongorc-file>`.

- All MongoDB :doc:`executable files </reference/program>` now support
  the ``--quiet`` option to suppress all logging output except for
  error messages.

- :binary:`~bin.mongoimport` uses the input filename, without the file
  extension if any, as the collection name if run without the ``-c`` or
  ``--collection`` specification.

- :binary:`~bin.mongoexport` can now constrain export data using
  :option:`--skip <mongoexport --skip>` and :option:`--limit <mongoexport --limit>`, as well as order the documents
  in an export using the :option:`--sort <mongoexport --sort>` option.

- :binary:`~bin.mongostat` can support the use of :option:`--rowcount <mongostat --rowcount>`
  (:option:`-n <mongostat -n>`) with the :option:`--discover <mongostat --discover>` option to produce the
  specified number of output lines.

- Add strict mode representation for :bsontype:`data_numberlong` for
  use by :binary:`~bin.mongoexport` and :binary:`~bin.mongoimport`.

MongoDB Enterprise Features
---------------------------

The following changes are specific to MongoDB Enterprise Editions:

MongoDB Enterprise for Windows
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

:doc:`MongoDB Enterprise for Windows
</tutorial/install-mongodb-enterprise-on-windows>` is now available. It
includes support for Kerberos, SSL, and SNMP.

.. include:: /includes/admonition-mongodb-enterprise-windows-ldap.rst

MongoDB Enterprise for Windows includes OpenSSL version 1.0.1g.

Auditing
~~~~~~~~

MongoDB Enterprise adds :doc:`auditing </core/auditing>` capability for
:binary:`~bin.mongod` and :binary:`~bin.mongos` instances. See :ref:`auditing`
for details.

.. _relnotes-ldap-authentication:

LDAP Support for Authentication
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

MongoDB Enterprise provides support for proxy authentication of users.
This allows administrators to configure a MongoDB cluster to
authenticate users by proxying authentication requests to a specified
Lightweight Directory Access Protocol (LDAP) service. See
:doc:`/tutorial/configure-ldap-sasl-openldap` and
:doc:`/tutorial/configure-ldap-sasl-activedirectory` for details.

.. include:: /includes/admonition-mongodb-enterprise-windows-ldap.rst

MongoDB does **not** support LDAP authentication in mixed sharded
cluster deployments that contain both version 2.4 and version 2.6
shards. See :doc:`/release-notes/2.6-upgrade` for upgrade instructions.

Expanded SNMP Support
~~~~~~~~~~~~~~~~~~~~~

MongoDB Enterprise has greatly expanded its SNMP support to provide
SNMP access to nearly the full range of metrics provided by
:method:`db.serverStatus()`.

.. seealso:: :ref:`2.6-snmp-iana-mib-incompatibility`

Additional Information
----------------------

Changes Affecting Compatibility
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. class:: hidden

   .. toctree::

      /release-notes/2.6-compatibility

Some changes in 2.6 can affect :doc:`compatibility
</release-notes/2.6-compatibility>` and may require user actions. The
2.6 :binary:`~bin.mongo` shell provides a
:method:`db.upgradeCheckAllDBs()` method to perform a check for upgrade
preparedness for some of these changes.

See :doc:`/release-notes/2.6-compatibility` for a detailed list of
compatibility changes.

.. seealso::
   `All Backwards incompatible changes (JIRA) <https://jira.mongodb.org/issues/?jql=project%20%3D%20SERVER%20AND%20fixVersion%20in%20(%222.5.0%22%2C%20%222.5.1%22%2C%20%222.5.2%22%2C%20%222.5.3%22%2C%20%222.5.4%22%2C%20%222.5.5%22%2C%20%222.6.0-rc1%22%2C%20%222.6.0-rc2%22%2C%20%222.6.0-rc3%22)%20AND%20%22Backwards%20Compatibility%22%20in%20(%20%22Minor%20Change%22%2C%22Major%20Change%22%20)%20ORDER%20BY%20votes%20DESC%2C%20issuetype%20DESC%2C%20key%20DESC>`_.

Upgrade Process
~~~~~~~~~~~~~~~

.. class:: hidden

   .. toctree::

      /release-notes/2.6-upgrade
      /release-notes/2.6-upgrade-authorization
      /release-notes/2.6-downgrade

See :doc:`/release-notes/2.6-upgrade` for full upgrade instructions.

Download
~~~~~~~~

To download MongoDB 2.6, go to the `downloads page`_.

.. TODO Should we add link to the installation guides?

.. _`downloads page`: http://www.mongodb.org/downloads

Other Resources
~~~~~~~~~~~~~~~

- `All JIRA issues resolved in 2.6 <https://jira.mongodb.org/secure/IssueNavigator.jspa?reset=true&jqlQuery=project+%3D+SERVER+AND+fixVersion+in+%28%222.5.0%22%2C+%222.5.1%22%2C+%222.5.2%22%2C+%222.5.3%22%2C+%222.5.4%22%2C+%222.5.5%22%2C+%222.6.0-rc1%22%2C+%222.6.0-rc2%22%2C+%222.6.0-rc3%22%29>`_.

- `All Third Party License Notices <https://github.com/mongodb/mongo/blob/v2.6/distsrc/THIRD-PARTY-NOTICES>`_.