[role="xpack"]
[[migration-api-assistance]]
=== Migration Assistance API

The Migration Assistance API analyzes existing indices in the cluster and returns the information
about indices that require some changes before the cluster can be upgraded to the next major version.

To see a list of indices that needs to be upgraded or reindexed, submit a GET request to the
`/_xpack/migration/assistance` endpoint:

[source,js]
--------------------------------------------------
GET /_xpack/migration/assistance
--------------------------------------------------
// CONSOLE
// TEST[skip:cannot create an old index in docs test]

A successful call returns a list of indices that need to updated or reindexed:

[source,js]
--------------------------------------------------
{
  "indices" : {
    ".watches" : {
      "action_required" : "upgrade"
    },
    ".security" : {
      "action_required" : "upgrade"
    },
    "my_old_index": {
      "action_required" : "reindex"
    },
    "my_other_old_index": {
      "action_required" : "reindex"
    }
  }
}
--------------------------------------------------
// NOTCONSOLE

To check a particular index or set of indices, specify this index name or mask as the last part of the
`/_xpack/migration/assistance/index_name` endpoint:

[source,js]
--------------------------------------------------
GET /_xpack/migration/assistance/my_*
--------------------------------------------------
// CONSOLE
// TEST[skip:cannot create an old index in docs test]

A successful call returns a list of indices that needs to updated or reindexed and match the index specified
on the endpoint:

[source,js]
--------------------------------------------------
{
  "indices" : {
    "my_old_index": {
      "action_required" : "reindex"
    },
    "my_other_old_index": {
      "action_required" : "reindex"
    }
  }
}
--------------------------------------------------
// NOTCONSOLE