elasticsearch/docs/reference/setup/important-settings/es-tmpdir.asciidoc

[[es-tmpdir]]
=== Temp directory

By default, Elasticsearch uses a private temporary directory that the startup
script creates immediately below the system temporary directory.

On some Linux distributions a system utility will clean files and directories
from `/tmp` if they have not been recently accessed. This can lead to the
private temporary directory being removed while Elasticsearch is running if
features that require the temporary directory are not used for a long time.
This causes problems if a feature that requires the temporary directory is
subsequently used.

If you install Elasticsearch using the `.deb` or `.rpm` packages and run it
under `systemd` then the private temporary directory that Elasticsearch uses
is excluded from periodic cleanup.

However, if you intend to run the `.tar.gz` distribution on Linux for an
extended period then you should consider creating a dedicated temporary
directory for Elasticsearch that is not under a path that will have old files
and directories cleaned from it. This directory should have permissions set
so that only the user that Elasticsearch runs as can access it. Then set the
`$ES_TMPDIR` environment variable to point to it before starting Elasticsearch.