This commit introduces a dedicated envirnoment variable ES_JAVA_HOME to
determine the JDK used to start (if not using the bundled JDK). This
environment variable will replace JAVA_HOME. The reason that we are
making this change is because JAVA_HOME is a common environment variable
and sometimes users have it set in their environment from other JDK
applications that they have installed on their system. In this case,
they would accidentally end up not using the bundled JDK despite their
intentions. By using a dedicated environment variable specific to
Elasticsearch, we avoid this potential for conflict. With this commit,
we introduce the new environment variable, and deprecate the use of
JAVA_HOME. We will remove support for JAVA_HOME in a future commit.
With the removal of support for older OSes, we no longer have any
supported systems which use SysV init. This commit removes support for
that legacy init system.
relates #51480
Some systems default to a nofile ulimit of 65535. To reduce the pain of
deploying Elasticsearch to such systems, this commit lowers the required
limit from 65536 to 65535.
The environment variable CONF_DIR was previously inconsistently used in
our packaging to customize the location of Elasticsearch configuration
files. The importance of this environment variable has increased
starting in 6.0.0 as it's now used consistently to ensure Elasticsearch
and all secondary scripts (e.g., elasticsearch-keystore) all use the
same configuration. The name CONF_DIR is there for legacy reasons yet
it's too generic. This commit renames CONF_DIR to ES_PATH_CONF.
Relates #26197
This commit removes the default path settings for data and logs. With
this change, we now ship the packages with these settings set in the
elasticsearch.yml configuration file rather than going through the
default.path.data and default.path.logs dance that we went through in
the past.
Relates #25408
The setting bootstrap.mlockall is useful on both POSIX-like systems
(POSIX mlockall) and Windows (Win32 VirtualLock). But mlockall is really
a POSIX only thing so the name should not be tied POSIX. This commit
renames the setting to "bootstrap.memory_lock".
Relates #18669
This commit adds a new configuration file jvm.options to centralize and
simplify management of JVM options. This separates the configuration of
the JVM from the packaging scripts (bin/elasticsearch*, bin/service.bat,
and init.d/elasticsearch) simplifying end-user operational management of
custom JVM options.