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Note
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This is only relevant for Linux. |
{es} uses the Java Native Access (JNA) library, and another library called
libffi, for executing some platform-dependent native code. On Linux, the
native code backing these libraries is extracted at runtime into a temporary
directory and then mapped into executable pages in {es}'s address space. This
requires the underlying files not to be on a filesystem mounted with the
noexec option.
By default, {es} will create its temporary directory within /tmp. However,
some hardened Linux installations mount /tmp with the noexec option by
default. This prevents JNA and libffi from working correctly. For instance,
at startup JNA may fail to load with an java.lang.UnsatisfiedLinkerError
exception or with a message that says something similar to
failed to map segment from shared object. Note that the exception message can
differ amongst JVM versions. Additionally, the components of {es} that rely on
execution of native code via JNA may fail with messages indicating that it is
because JNA is not available.
To resolve these problems, either remove the noexec option from your /tmp
filesystem, or configure {es} to use a different location for its temporary
directory by setting the $ES_TMPDIR environment variable. For
instance:
export ES_TMPDIR=/usr/share/elasticsearch/tmpAlternatively, you can configure the path that JNA uses for its temporary files
with the JVM flag -Djna.tmpdir=<path> and you can
configure the path that libffi uses for its temporary files with the
LIBFFI_TMPDIR environment variable.