[[breaking-changes-6.0]]
== Breaking changes in 6.0

This section discusses the changes that you need to be aware of when migrating
your application to Elasticsearch 6.0.

[float]
=== Indices created before 6.0

Elasticsearch 6.0 can read indices created in version 5.0 or above.  An
Elasticsearch 6.0 node will not start in the presence of indices created in a
version of Elasticsearch before 5.0.

[IMPORTANT]
.Reindex indices from Elasticseach 2.x or before
=========================================

Indices created in Elasticsearch 2.x or before will need to be reindexed with
Elasticsearch 5.x in order to be readable by Elasticsearch 6.x. The easiest
way to reindex old indices is to use the `reindex` API.

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

[float]
=== Also see:

* <<breaking_60_rest_changes>>
* <<breaking_60_search_changes>>
* <<breaking_60_docs_changes>>
* <<breaking_60_cluster_changes>>
* <<breaking_60_settings_changes>>
* <<breaking_60_plugins_changes>>

include::migrate_6_0/rest.asciidoc[]

include::migrate_6_0/search.asciidoc[]

include::migrate_6_0/docs.asciidoc[]

include::migrate_6_0/cluster.asciidoc[]

include::migrate_6_0/settings.asciidoc[]

include::migrate_6_0/plugins.asciidoc[]