[[executable-jna-tmpdir]] === JNA temporary directory not mounted with `noexec` [NOTE] 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 <> environment variable. For instance: ["source","sh",subs="attributes"] -------------------------------------------- export ES_TMPDIR=/usr/share/elasticsearch/tmp -------------------------------------------- Alternatively, you can configure the path that JNA uses for its temporary files with the <> `-Djna.tmpdir=` and you can configure the path that `libffi` uses for its temporary files with the `LIBFFI_TMPDIR` environment variable.