Where to configure systems settings depends on which package you have used to install Elasticsearch, and which operating system you are using.
When using the
.tar.gz packages, system settings can be configured:
When using the RPM or Debian packages, most system settings are set in the system configuration file. However, systems which use systemd require that system limits are specified in a systemd configuration file.
On Linux systems,
ulimit can be used to change resource limits on a
temporary basis. Limits usually need to be set as
root before switching to
the user that will run Elasticsearch. For example, to set the number of
open file handles (
ulimit -n) to 65,536, you can do the following:
Change the max number of open files.
The new limit is only applied during the current session.
You can consult all currently applied limits with
On Linux systems, persistent limits can be set for a particular user by
/etc/security/limits.conf file. To set the maximum number of
open files for the
elasticsearch user to 65,536, add the following line to
elasticsearch - nofile 65536
This change will only take effect the next time the
elasticsearch user opens
a new session.
Ubuntu ignores the
limits.conf file for processes started by
limits.conf file, edit
/etc/pam.d/su and uncomment the
# session required pam_limits.so
When using the RPM or Debian packages, system settings and environment variables can be specified in the system configuration file, which is located in:
However, for systems which uses
systemd, system limits need to be specified
When using the RPM or Debian packages on systems that use systemd, system limits must be specified via systemd.
The systemd service file (
contains the limits that are applied by default.
To override these, add a file called
/etc/systemd/system/elasticsearch.service.d/elasticsearch.conf and specify
any changes in that file, such as:
The preferred method of setting Java Virtual Machine options (including
system properties and JVM flags) is via the
file. The default location of this file is
installing from the tar or zip distributions) and
/etc/elasticsearch/jvm.options (when installing from the Debian or RPM
packages). This file contains a line-delimited list of JVM arguments,
which must begin with
-. You can add custom JVM flags to this file and
check this configuration into your version control system.
An alternative mechanism for setting Java Virtual Machine options is
ES_JAVA_OPTS environment variable. For instance:
export ES_JAVA_OPTS="$ES_JAVA_OPTS -Djava.io.tmpdir=/path/to/temp/dir" ./bin/elasticsearch
When using the RPM or Debian packages,
ES_JAVA_OPTS can be specified in the
system configuration file.
The JVM has a built-in mechanism for observing the
environment variable. We intentionally ignore this environment variable in our
packaging scripts. The primary reason for this is that on some OS (e.g., Ubuntu)
there are agents installed by default via this environment variable that we do
not want interfering with Elasticsearch.
Additionally, some other Java programs support the
variable. This is not a mechanism built into the JVM but instead a convention
in the ecosystem. However, we do not support this environment variable, instead
supporting setting JVM options via the
jvm.options file or the environment
ES_JAVA_OPTS as above.