[[breaking-changes-5.0]]
== Breaking changes in 5.0

This section discusses the changes that you need to be aware of when migrating
your application to Elasticsearch 5.0.

[float]
=== Indices created before 5.0

Elasticsearch 5.0 can read indices created in version 2.0 and above.  If any
of your indices were created before 2.0 you will need to upgrade to the
latest 2.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. To upgrade 2.x indices, first start a node which have access to all
the data folders and let it upgrade all the indices before starting up rest of
the cluster.

[IMPORTANT]
.Reindex indices from Elasticseach 1.x or before
=========================================

Indices created in Elasticsearch 1.x or before will need to be reindexed with
Elasticsearch 2.x in order to be readable by Elasticsearch 5.x. The easiest
way to do this is to upgrade to Elasticsearch 2.3 or later and to use the
`reindex` API.

=========================================

[float]
=== Also see:

* <<breaking_50_search_changes>>
* <<breaking_50_mapping_changes>>
* <<breaking_50_percolator>>
* <<breaking_50_index_apis>>
* <<breaking_50_settings_changes>>
* <<breaking_50_allocation>>
* <<breaking_50_rest_api_changes>>
* <<breaking_50_cat_api>>
* <<breaking_50_java_api_changes>>
* <<breaking_50_packaging>>
* <<breaking_50_plugins>>
* <<breaking_50_fs>>
* <<breaking_50_aggregations_changes>>


include::migrate_5_0/search.asciidoc[]

include::migrate_5_0/mapping.asciidoc[]

include::migrate_5_0/percolator.asciidoc[]

include::migrate_5_0/index-apis.asciidoc[]

include::migrate_5_0/settings.asciidoc[]

include::migrate_5_0/allocation.asciidoc[]

include::migrate_5_0/rest.asciidoc[]

include::migrate_5_0/cat.asciidoc[]

include::migrate_5_0/java.asciidoc[]

include::migrate_5_0/packaging.asciidoc[]

include::migrate_5_0/plugins.asciidoc[]

include::migrate_5_0/fs.asciidoc[]

include::migrate_5_0/aggregations.asciidoc[]