WARNING: Version 5.5 of Elasticsearch has passed its EOL date.
This documentation is no longer being maintained and may be removed. If you are running this version, we strongly advise you to upgrade. For the latest information, see the current release documentation.
Packaging
editPackaging
editAPT/YUM repository URL changes
editThe repository for apt and yum packages has changed from
https://packages.elastic.co
to https://artifacts.elastic.co/
.
Full details can be found in Installing Elasticsearch.
Default logging using systemd (since Elasticsearch 2.2.0)
editIn previous versions of Elasticsearch, the default logging configuration routed standard output to /dev/null and standard error to the journal. However, there are often critical error messages at startup that are logged to standard output rather than standard error and these error messages would be lost to the nether. The default has changed to now route standard output to the journal and standard error to inherit this setting (these are the defaults for systemd). These settings can be modified by editing the elasticsearch.service file.
Longer startup times
editIn Elasticsearch 5.0.0 the -XX:+AlwaysPreTouch
flag has been added to the JVM
startup options. This option touches all memory pages used by the JVM heap
during initialization of the HotSpot VM to reduce the chance of having to commit
a memory page during GC time. This will increase the startup time of
Elasticsearch as well as increasing the initial resident memory usage of the
Java process.
JVM options
editArguments to the Java Virtual Machine have been centralized and moved to a new configuration file jvm.options. This centralization allows for simpler end-user management of JVM options.
This migration removes all previous mechanisms of setting JVM options
via the environment variables ES_MIN_MEM
, ES_MAX_MEM
,
ES_HEAP_SIZE
, ES_HEAP_NEWSIZE
, ES_DIRECT_SIZE
, ES_USE_IPV4
,
ES_GC_OPTS
, ES_GC_LOG_FILE
, and JAVA_OPTS
.
The default location for this file is in config/jvm.options if installing
from the tar or zip distributions, and /etc/elasticsearch/jvm.options if installing
from the Debian or RPM packages. You can specify an alternative location by setting
the environment variable ES_JVM_OPTIONS
to the path to the file.
Thread stack size for the Windows service
editPreviously when installing the Windows service, the installation script would configure the thread stack size (this is required for the service daemon). As a result of moving all JVM configuration to the jvm.options file, the service installation script no longer configures the thread stack size. When installing the Windows service, you must configure thread stack size. For additional details, see the installation docs.
/bin/bash is now required
editPreviously, the scripts used to start Elasticsearch and run plugin
commands only required a Bourne-compatible shell. Starting in
Elasticsearch 5.0.0, the bash shell is now required and /bin/bash
is a
hard-dependency for the RPM and Debian packages.
Environmental Settings
editPreviously, Elasticsearch could be configured via environment variables
in two ways: first by using the placeholder syntax
${env.ENV_VAR_NAME}
and the second by using the same syntax without
the env
prefix: ${ENV_VAR_NAME}
. The first method has been removed
from Elasticsearch.
Additionally, it was previously possible to set any setting in Elasticsearch via JVM system properties. This has been removed from Elasticsearch.
Dying on fatal errors
editPrevious versions of Elasticsearch would not halt the JVM if out of memory errors or other fatal errors were encountered during the life of the Elasticsearch instance. Because such errors leave the JVM in a questionable state, the best course of action is to halt the JVM when this occurs. Starting in Elasticsearch 5.x, this is now the case. Operators should consider configuring their Elasticsearch services so that they respawn automatically in the case of such a fatal crash.