[[breaking-changes-2.0]]
== Breaking changes in 2.0

This section discusses the changes that you need to be aware of when migrating
your application to Elasticsearch 2.0.

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=== Indices created before 0.90

Elasticsearch 2.0 can read indices created in version 0.90 and above.  If any
of your indices were created before 0.90 you will need to upgrade to the
latest 1.x version of Elasticsearch first, in order to upgrade your indices or
to delete the old indices. Elasticsearch will not start in the presence of old
indices.

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=== Elasticsearch migration plugin

We have provided the https://github.com/elastic/elasticsearch-migration[Elasticsearch migration plugin]
to help you detect any issues that you may have when upgrading to
Elasticsearch 2.0. Please install and run the plugin *before* upgrading.

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=== Also see

* <<breaking_20_removed_features>>
* <<breaking_20_network_changes>>
* <<breaking_20_multiple_literal_data_path_literal_striping>>
* <<breaking_20_mapping_changes>>
* <<breaking_20_crud_and_routing_changes>>
* <<breaking_20_query_dsl_changes>>
* <<breaking_20_search_changes>>
* <<breaking_20_aggregation_changes>>
* <<breaking_20_parent_child_changes>>
* <<breaking_20_scripting_changes>>
* <<breaking_20_index_api_changes>>
* <<breaking_20_snapshot_and_restore_changes>>
* <<breaking_20_plugin_and_packaging_changes>>
* <<breaking_20_setting_changes>>
* <<breaking_20_stats_info_and_literal_cat_literal_changes>>
* <<breaking_20_java_api_changes>>

include::migrate_2_0/removals.asciidoc[]

include::migrate_2_0/network.asciidoc[]

include::migrate_2_0/striping.asciidoc[]

include::migrate_2_0/mapping.asciidoc[]

include::migrate_2_0/crud.asciidoc[]

include::migrate_2_0/query_dsl.asciidoc[]

include::migrate_2_0/search.asciidoc[]

include::migrate_2_0/aggs.asciidoc[]

include::migrate_2_0/parent_child.asciidoc[]

include::migrate_2_0/scripting.asciidoc[]

include::migrate_2_0/index_apis.asciidoc[]

include::migrate_2_0/snapshot_restore.asciidoc[]

include::migrate_2_0/packaging.asciidoc[]

include::migrate_2_0/settings.asciidoc[]

include::migrate_2_0/stats.asciidoc[]

include::migrate_2_0/java.asciidoc[]