This adds `-XX:-OmitStackTraceInFastThrow` to the JVM arguments
which *should* prevent the JVM from omitting stack traces on
common exception sites. Even though these sites are common, we'd
still like the exceptions to debug them.
This also adds the flag when running tests and adapts some tests
that had workarounds for the absense of the flag.
Closes#24376
After the removal of the joda time hack we used to have, we can cleanup
the codebase handling in security, jarhell and plugins to be more picky
about uniqueness. This was originally in #18959 which was never merged.
closes#18959
Today when users start Elasticsearch with their Java configuration
pointing to a pre-Java 8 install, they encounter a cryptic message:
Exception in thread "main" java.lang.UnsupportedClassVersionError:
org/elasticsearch/bootstrap/Elasticsearch : Unsupported major.minor
version 52.0
They often think that they have Java 8 installed but if their JAVA_HOME
or other configuration is causing them to start with a pre-Java 8
install, this error message does not help them.
We introduce a Java version checker that runs on Java 6 as part of the
startup scripts. If the Java version is pre-Java 8, we can display a
helpful error message to the user informing them of the Java version
that the runtime was started with. Otherwise, Elasticsearch starts as it
does today.
By default, the JVM GC log file grows without
limitation. This is inconvenient for a long running
process like Elasticsearch.
With this commit we add an example configuration
for a rotating GC log in `conig/jvm.options`.
For certain situations, end-users need the base path for Elasticsearch
logs. Exposing this as a property is better than hard-coding the path
into the logging configuration file as otherwise the logging
configuration file could easily diverge from the Elasticsearch
configuration file. Additionally, Elasticsearch will only have
permissions to write to the log directory configured in the
Elasticsearch configuration file. This commit adds a property that
exposes this base path.
One use-case for this is configuring a rollover strategy to retain logs
for a certain period of time. As such, we add an example of this to the
documentation.
Additionally, we expose the property es.logs.cluster_name as this is
used as the name of the log files in the default configuration.
Finally, we expose es.logs.node_name in cases where node.name is
explicitly set in case users want to include the node name as part of
the name of the log files.
Relates #22625
The config template that ships with Elasticsearch distributions contains
links to various pieces of documentation. Links go out of date and get
broken. This commit removes such links from the config template.
Relates #22553
This commit reverts switching to the unpooled allocator (for now) to let
some benchmarks run to see if this is the source of an increase in GC
times.
Relates #22452
Netty plays a lot of games with recycling byte buffers in thread local
caches, and using a pooled byte buffer allocator to reduce pressure on
the garbage collector.
The recycler in particular appears to be fraught with peril. It appears
that there are circumstances where the recycler does not recycle quickly
enough and can exceed its capacity leading to heap exhaustion and out of
memory errors. If you spend a few minutes reading the history of the
recycler on the Netty GitHub issues, it appears it has been nothing but
a source of trouble, and the project itself has an open issue that
proposes disabling by default and possibly even removing the recycler.
The pooled byte buffer allocator has problems itself. It sizes the pool
based on the number of runtime processors and can indeed grab a very
large percentage of the heap (in some cases 50% or more). Additionally,
the Netty project continues to struggle with leaks here.
We are seeing users struggle with issues in 5.x that I think are largely
driven by some of the problems here with Netty.
This change proposes to disable the recycler, and to disable the pooled
byte buffer allocator. I think that disabling these features will return
some of the stablity that these features appear to be losing us.
I have done performance testing on my workstation with disabling these
and I do not see a difference in performance. I propose that we make
this change in master and let some nightly benchmarks run to confirm
that there is not a difference in performance. If we are comfortable
with the performance changes, I propose backporting this to all active
branches.
Relates #22452
This change is the first towards providing the ability to store
sensitive settings in elasticsearch. It adds the
`elasticsearch-keystore` tool, which allows managing a java keystore.
The keystore is loaded upon node startup in Elasticsearch, and used by
the Setting infrastructure when a setting is configured as secure.
There are a lot of caveats to this PR. The most important is it only
provides the tool and setting infrastructure for secure strings. It does
not yet provide for keystore passwords, keypairs, certificates, or even
convert any existing string settings to secure string settings. Those
will all come in follow up PRs. But this PR was already too big, so this
at least gets a basic version of the infrastructure in.
The two main things to look at. The first is the `SecureSetting` class,
which extends `Setting`, but removes the assumption for the raw value of the
setting to be a string. SecureSetting provides, for now, a single
helper, `stringSetting()` to create a SecureSetting which will return a
SecureString (which is like String, but is closeable, so that the
underlying character array can be cleared). The second is the
`KeyStoreWrapper` class, which wraps the java `KeyStore` to provide a
simpler api (we do not need the entire keystore api) and also extend
the serialized format to add metadata needed for loading the keystore
with no assumptions about keystore type (so that we can change this in
the future) as well as whether the keystore has a password (so that we
can know whether prompting is necessary when we add support for keystore
passwords).
A previous fix for the handling of paths on Windows related to paths
containing multiple spaces introduced a issue where if JAVA_HOME ends
with a backslash, then Elasticsearch will refuse to start. This is not a
critical bug as a workaround exists (remove the trailing backslash), but
should be fixed nevertheless. This commit addresses this situation while
not regressing the previous fix.
Relates #22132
This commit fixes the handling of spaces in Windows paths. The current
mechanism works fine in a path that contains a single space, but fails
on a path that contains multiple spaces. With this commit, that is no
longer the case.
Relates #21921
Elasticsearch can be run in a few different ways:
- from the command line on Linux and Windows
- as a service on Linux and Windows
on both 32-bit client and 64-bit server VMs. We strive for a great
out-of-the-box experience any of these combinations but today it is
lacking on 32-bit client JVMs and on the Windows service. There are two
deficiencies that arise:
- on any 32-bit client JVM we fail to start out of the box because we
force the server JVM in jvm.options
- when installing the Windows service, the thread stack size must be
specified in jvm.options
This commit attempts to address these deficiencies.
We should continue to force the server JVM because there are systems
where the server JVM is not active by default (e.g., the 32-bit JDK on
Windows). This does mean that if a user tries to run with a client JVM
they will see a failure message at startup but this is the best that we
can do if we want to continue to force the server JVM. Thus, this commit
at least documents this situation.
To improve the situation with installing the Windows service, this
commit adds a default setting for the thread stack size. This default is
chosen based on the default thread stack size across all 64-bit server
JVMs. This means that if a user tries to run with a 32-bit JVM they
could otherwise see significantly higher memory usage (this situation is
complicated, it's really only on Windows where the extra memory usage is
egregious, but cutting into the 32-bit address space on any system is
bad). So this commit makes it so that the out-of-the-box experience is
improved for the Windows service on 64-bit server JVMs and we document
the need to adjust this setting on 32-bit JVMs.
Again, we are focusing on the out-of-the-box experience here and this
means optimizing for the best experience on any 64-bit server JVM as
this covers the vast majority of the user base. The users that are on
32-bit JVMs will suffer a little bit but at least now any user on any
64-bit server JVM can start Elasticsearch out of the box.
Finally, we fix some references to the jvm.options documentation.
Relates #21920
During package install on systemd-based systems, we try to set
vm.max_map_count. On some systems (e.g., containers), users do not have
the ability to tune these parameters from within the container. This
commit provides an option for these users to skip setting such kernel
parameters.
Relates #21899
Our default pattern layout truncates log messages. This is to avoid
blowing disk space from excessively log messages, which can happen if a
message contains a mapping or an large query. Yet, we trunacte from the
beginning which is probably where the most germane information is. This
commit modifies the default pattern layout to trunacte from the end.
Relates #21609
On some systems these utilities are in /usr/lib/systemd/systemd-sysctl
and /usr/sbin/sysctl, and on others the /usr is dropped. This commit
accounts for that fact.
Our docs claim that we set vm.max_map_count automatically. This is not
quite the case. The story is that on SysV init we set vm.max_map_count
each time the service starts, which is good. On systemd, we create a
sysctl.d conf file that sets vm.map_max_count, but this is only
meaningful if the system is rebooted after package install. This commit
modifies the post-install script so that we run systemd-sysctl so that
the vm.max_map_count change occurs after package install without a
reboot.
Relates #21507
Given that the default is now 1, the comment in the config file was outdated. Also considering that the default value is production ready, we shouldn't list it among the values that need attention when going to production.
Relates to #19964
When installing the Windows service, certain settings like the minimum
heap, maximum heap and thread stack size setting must be set. While
there is an error message making mention of this fact, the error message
is not explicit exactly what setting needs to be set. This commit makes
these settings explicit.
Relates #21200
Currently we always pass -E to the the plugin cli with the conf dir, but
this causes a very confusing error message when not giving a specific
command to the plugin cli. This change makes path.conf pass just like
path.home. These are special settings, so passing via sysprops is the
right thing to do (it is all about how we pass between shell and java
cli).
closes#18689
When upgrading elasticsearch using the RPM package, the scripts directory is removed if it's empty but it won't be recreated by the upgraded package. But after that the service won't start because the scripts dir is missing.
This commit modifies the logger names within Elasticsearch to be the
fully-qualified class name as opposed removing the org.elasticsearch
prefix and dropping the class name. This change separates the root
logger from the Elasticsearch loggers (they were equated from the
removal of the org.elasticsearch prefix) and enables log levels to be
set at the class level (instead of the package level).
Relates #20457
Today we add a prefix when logging within Elasticsearch. This prefix
contains the node name, and index and shard-level components if
appropriate.
Due to some implementation details with Log4j 2 , this does not work for
integration tests; instead what we see is the node name for the last
node to startup. The implementation detail here is that Log4j 2 there is
only one logger for a name, message factory pair, and the key derived
from the message factory is the class name of the message factory. So,
when the last node starts up and starts setting prefixes on its message
factories, it will impact the loggers for the other nodes.
Additionally, the prefixes are lost when logging an exception. This is
due to another implementation detail in Log4j 2. Namely, since we log
exceptions using a parameterized message, Log4j 2 decides that that
means that we do not want to use the message factory that we have
provided (the prefix message factory) and so logs the exception without
the prefix.
This commit fixes both of these issues.
Relates #20429
This commit adds a -q/--quiet option to Elasticsearch so that it does not log anything in the console and closes stdout & stderr streams. This is useful for SystemD to avoid duplicate logs in both journalctl and /var/log/elasticsearch/elasticsearch.log while still allows the JVM to print error messages in stdout/stderr if needed.
closes#17220
The Elasticsearch startup scripts contain checks for the presence of
support for environment variables that were removed in the 5.x
series. These checks warn the user and fail the script if any of the
unsupported environment variables are present. This was provided as
migration step from 2.x to 5.x so that we were not just silently
ignoring environment variables that were previously set. This commit
removes these checks, as upgrades from 2.x to 6.x are not supported.
Relates #20404
Previous versions of Elasticsearch permitted unquoted JSON field names even though this is against the JSON spec. This leniency was disabled by default in the 5.x series of Elasticsearch but a backwards compatibility layer was added via a system property with the intention of removing this layer in 6.0.0. This commit removes this backwards compatibility layer.
Relates #20388
-D parameters used to be allowed when starting elasticsearch scripts.
However, this was removed in #18207, but the elasticsearch-plugin.bat script
was forgotten. This change removes the -D handling.
Jython shades `jansi` into it's classpath without changing it's package or
anything like that. This causes attempts to load native code on windows which
blows up tests. This change adds `log4j.skipJansi=true` system property to our
tests as well as to the JVM properties we set.
This commit configures the deprecation logs to be size-limited to 1 GB,
and compress these logs when they roll. The default configuration will
preserve up to four rolled logs.
Relates #20287
* master:
Increase visibility of deprecation logger
Skip transport client plugin installed on JDK 9
Explicitly disable Netty key set replacement
percolator: Fail indexing percolator queries containing either a has_child or has_parent query.
Make it possible for Ingest Processors to access AnalysisRegistry
Allow RestClient to send array-based headers
Silence rest util tests until the bogusness can be simplified
Remove unknown HttpContext-based test as it fails unpredictably on different JVMs
Tests: Improve rest suite names and generated test names for docs tests
Add support for a RestClient base path
The deprecation logger is an important way to make visible features of
Elasticsearch that are deprecated. Yet, the default logging makes the
log messages for the deprecation logger invisible. We want these log
messages to be visible, so the default logging for the deprecation
logger should enable these log messages. This commit changes the log
level of deprecation log message to warn, and configures the deprecation
logger so that these log messages are visible out of the box.
Relates #20254
Netty replaces the backing set for the selector implementation. The
value of doing this is questionable, and doing this requires permissions
that we are not going to grant. This commit explicitly disables this
optimization rather than relying on it failing due to lack of
permissions.
Relates #20249
the setting in elasticsearch.yml, so that when a user uncomments
out a setting by just removing the #, the setting actually
takes effect. Before, it was very easy to uncomment out a
setting by just removing the #, leaving a single whitespace
character before the setting name, which would cause the
setting to not get picked up by Elasticsearch.
Closes#20090
This commit fixes the handling of spaces in the path to the jvm.options
file on Windows. The issue is that the extraneous set of quotes were
included as part of the value of ES_JVM_OPTIONS thus confusing further
downstream commands.
Relates #19951
With the security permissions that we grant to Netty, Netty can not
access unsafe (because it relies on having the runtime permission
accessDeclaredMembers and the reflect permission
suppressAccessChecks). Instead, we should just explicitly tell Netty to
not use unsafe. This commit adds a flag to the default jvm.options to
tell Netty to not look for unsafe.
Relates #19786
This adds the `bin/elasticsearch-translate` bin file that will be used
for CLI tasks pertaining to Elasticsearch. Currently it implements only
a single sub-command, `truncate-translog`, that creates a truncated
translog for a given folder.
Here's what running the tool looks like:
```
λ bin/elasticsearch-translog truncate -d data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/
Checking existing translog files
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
! WARNING: Elasticsearch MUST be stopped before running this tool !
! !
! WARNING: Documents inside of translog files will be lost !
! !
! WARNING: The following files will be DELETED! !
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
--> data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/translog-10.tlog
--> data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/translog-18.tlog
--> data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/translog-21.tlog
--> data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/translog-12.ckp
--> data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/translog-25.ckp
--> data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/translog-29.tlog
--> data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/translog-2.tlog
--> data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/translog-5.tlog
--> data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/translog-41.ckp
--> data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/translog-6.ckp
--> data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/translog-37.ckp
--> data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/translog-24.ckp
--> data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/translog-11.ckp
Continue and DELETE files? [y/N] y
Reading translog UUID information from Lucene commit from shard at [data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/index]
Translog Generation: 3
Translog UUID : AxqC4rocTC6e0fwsljAh-Q
Removing existing translog files
Creating new empty checkpoint at [data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/translog.ckp]
Creating new empty translog at [data/nodes/0/indices/P45vf_YQRhqjfwLMUvSqDw/0/translog/translog-3.tlog]
Done.
```
It also includes a `-b` batch operation that can be used to skip the
confirmation diaglog.
Resolves#19123
Today in the packaging removal scripts, we disable the service in
post-uninstall. Yet, this happens after service files have been
erased. On some systems, this can cause the service disable to fail
leaving behind state causing the service to be enabled on subsequent
installs. This commit moves the service disabling to the pre-uninstall
script to prevent this issue.
Relates #19328
Unless explicitly disabled, the parallel new collector is enabled
automatically as soon as the CMS collector is enabled:
void Arguments::set_cms_and_parnew_gc_flags() {
assert(
!UseSerialGC && !UseParallelOldGC && !UseParallelGC,
"Error");
assert(UseConcMarkSweepGC, "CMS is expected to be on here");
// If we are using CMS, we prefer to UseParNewGC,
// unless explicitly forbidden.
if (FLAG_IS_DEFAULT(UseParNewGC)) {
FLAG_SET_ERGO(bool, UseParNewGC, true);
}
While it's fine to be explicit, the UseParNewGC flag is deprecatd in JDK
8 and produces warning messages in JDK 9:
Java HotSpot(TM) 64-Bit Server VM warning: Option UseParNewGC was
deprecated in version 9.0 and will likely be removed in a future
release.
Thus, we can and should just remove this flag from the default JVM
options.
Relates #18767
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
The distributions had their own copies of these extra files, which was a
carry over from maven. This change removes the duplicate files and
copies them from the root of the project.
closes#18597
The default jvm.options file ships with the -server flag to force the
server VM on systems where the server VM is not the default. However,
the method of starting the JVM via the Windows service does not support
the command-line flags for selecting the VM because it starts from a
DLL that is specific to the server or client VM. Thus, we need to
filter these options from the jvm.options configuration file when
installing the Windows service.
Relates #18473
Today when parsing settings during bootstrap, we add a system property
for every Elasticsearch setting. Additionally, settings can be set via
system properties. This commit simplifies this situation.
- settings are no longer propogated to system properties
- system properties can not be used to set settings
- the "es." prefix on settings is no longer required (nor permitted)
- test logging has a dedicated system property (tests.logger.level)
Relates #18198
In the plugin script we set the setting default.path.conf to control the
path to the configuration file. But the default directory might not
exist in which case we can run into exceptions. This commit restores a
guard against this directory not existing.
This commit switches the command-line scripts to use bash instead of sh
so that we can take advantage of features that bash provides like
arrays.
Relates #18251
In 7d1fd17172 the parsing of command-line
properties in the plugin script was removed. That commit missed
additional parsing of the properties for es.default.path.conf. This
commit removes that parsing and also replaces the use of eval with exec.
Relates #18239
The plugin script parses command-line options looking for Java system
properties and extracts these arguments to pass to the java command when
starting the JVM. Since elasticsearch-plugin allows arbitrary user
arguments to the JVM via ES_JAVA_OPTS, this parsing is unnecessary. This
commit removes this unnecessary
Relates #18207
Today we softly warn about running with the client VM. However, we
should really refuse to start in production mode if running with the
client VM as the performance of the client VM is too devastating for a
server application. This commit adds an option to jvm.options to ensure
that we are starting with the server VM (on all 32-bit non-Windows
platforms on server-class machines (2+ CPUs, 2+ GB physical RAM) this is
the default and on all 64-bit platforms this is the only option) and
adds a bootstrap check for the client VM.
Relates #18155
Today we specify the client option for the JVM when executing plugin
commands. Yet, this option does nothing on a 64-bit capable JDK as such
JDKs always select the Hotspot server VM. And for 32-bit JDKs, running
plugin commands with the server VM is okay. Thus, we should just remove
this unnecessary flag and just let the default VM be selected.
Relates #18142
This changes our packaging to be explicit about the permissions of files
and directories in the tar.gz, rpm, and deb packages. This is to protect
against a user having an incorrectly set umask when installing.
Additionally, plugins that are installed now have their permissions set
by the plugin installation so that plugins that may have been packaged
with incorrect permissions are secured.
Resolves#17634
In Elasticsearch 5.0.0, by default unquoted field names in JSON will be
rejected. This can cause issues, however, for documents that were
already indexed with unquoted field names. To alleviate this, a system
property has been added that can be enabled so migration can occur.
This system property will be removed in Elasticsearch 6.0.0
Resolves#17674
This commit simplifies the default JVM options that ship with
Elasticsearch. In particular, expert settings that were previously
configurable via environment variables have been removed from the
default configuration file. Further, the heap size settings have been
moved to the top of the file with a clearer message that is in
concordance with their importance.
Closes#17714
This commit sets the bad_env_var to a default value of 0 so that in case
no bad environment variables are encountered the variable is still
defined and does not later cause a parse error in the execution of these
batch files.
Relates #17675
JAVA_OPTS is not a built-in mechanism for passing options to the JVM but
many people think that it is. We do not respect JAVA_OPTS, but this
commit adds a warning if it is set in case the end-user thinks that it
will affect Elasticsearch.
This commit renames the function that parses JVM options in
bin/elasticsearch from jvm_options to parse_jvm_options. The reason for
the rename is because a for-loop variable was shadowing the name of this
function and changing the function name further clarifies the purpose of
the function.
This commit fixes the placement of a comment in bin/elasticsearch. The
comment was made out of place by the addition of a function definition
but order is restored.
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.
This commit quotes the variable that contains the path to the java
binary. Without these quotes, when the arguments to eval are evaluated
the existing quotes will be removed leading to unquoted use of the path
to the java binary. If this path contains spaces, evaluation will fail.
This commit ensures that the data, logs, and config directories have the
proper ownership after the packages are installed. Additionally, this
commit ensures that the configs in /etc/elasticsearch are preserved
after removal of the RPM package.
This commit fixes the pidfile setting on systems that used systemd. The
issue is that the pidfile can only be set via the command line arguments
-p or --pidfile, and is no longer settable via a setting.
Today, certain bootstrap properties are set and read via system
properties. This action-at-distance way of managing these properties is
rather confusing, and completely unnecessary. But another problem exists
with setting these as system properties. Namely, these system properties
are interpreted as Elasticsearch settings, not all of which are
registered. This leads to Elasticsearch failing to startup if any of
these special properties are set. Instead, these properties should be
kept as local as possible, and passed around as method parameters where
needed. This eliminates the action-at-distance way of handling these
properties, and eliminates the need to register these non-setting
properties. This commit does exactly that.
Additionally, today we use the "-D" command line flag to set the
properties, but this is confusing because "-D" is a special flag to the
JVM for setting system properties. This creates confusion because some
"-D" properties should be passed via arguments to the JVM (so via
ES_JAVA_OPTS), and some should be passed as arguments to
Elasticsearch. This commit changes the "-D" flag for Elasticsearch
settings to "-E".
Enables the touching of all memory pages used by the JVM heap spaces
during initialization of the HotSpot VM, which commits all memory pages
at initialization time. By default, pages are committed only as they are
needed.
The plugin cli currently is extremely lenient, allowing most errors to
simply be logged. This can lead to either corrupt installations (eg
partially installed plugins), or confused users.
This change rewrites the plugin cli to have almost no leniency.
Unfortunately it was not possible to remove all leniency, due in
particular to how config files are handled.
The following functionality was simplified:
* The format of the name argument to install a plugin is now an official
plugin name, maven coordinates, or a URL.
* Checksum files are required, and only checked, for official plugins
and maven plugins. Checksums are also only SHA1.
* Downloading no longer uses a separate thread, and no longer has a timeout.
* Installation, and removal, attempts to be atomic. This only truly works
when no config or bin files exist.
* config and bin directories are verified before copying is attempted.
* Permissions and user/group are no longer set on config and bin files.
We rely on the users umask.
* config and bin directories must only contain files, no subdirectories.
* The code is reorganized so each command is a separate class. These
classes already existed, but were embedded in the plugin cli class, as
an extra layer between the cli code and the code running for each command.
This commit modifies the default setting for standard output in the
systemd configuration to the journal instead of /dev/null. This is to
address a user pain point where Elasticsearch would fail to start but
the error message would be sent to standard output and therefore
/dev/null leading to difficult-to-debug situations.