[role="xpack"]
[testenv="basic"]
[[freeze-index-api]]
=== Freeze index API
++++
<titleabbrev>Freeze index</titleabbrev>
++++

Freezes an index.

[[freeze-index-api-request]]
==== {api-request-title}

`POST /<index>/_freeze`

//[[freeze-index-api-prereqs]]
//==== {api-prereq-title}

[[freeze-index-api-desc]]
==== {api-description-title}

A frozen index has almost no overhead on the cluster (except for maintaining its
metadata in memory) and is read-only. Read-only indices are blocked for write
operations, such as <<indexing,docs-index_>> or <<indices-forcemerge,force
merges>>. See <<frozen-indices>> and <<unfreeze-index-api>>.

The current write index on a data stream cannot be frozen. In order to freeze
the current write index, the data stream must first be
<<rollover-data-stream-ex,rolled over>> so that a new write index is created
and then the previous write index can be frozen.

IMPORTANT: Freezing an index will close the index and reopen it within the same
API call. This causes primaries to not be allocated for a short amount of time
and causes the cluster to go red until the primaries are allocated again. This
limitation might be removed in the future.

[[freeze-index-api-path-parms]]
==== {api-path-parms-title}

`<index>`::
  (Required, string) Identifier for the index.

[[freeze-index-api-examples]]
==== {api-examples-title}

The following example freezes and unfreezes an index:

[source,console]
--------------------------------------------------
POST /my-index-000001/_freeze
POST /my-index-000001/_unfreeze
--------------------------------------------------
// TEST[s/^/PUT my-index-000001\n/]