OpenSSL Troubleshooting

Check that you have enabled OpenSSL in elasticsearch.yml (which is the default)

  • searchguard.ssl.transport.enable_openssl_if_available: true
  • searchguard.ssl.http.enable_openssl_if_available: true

If you did all the steps above and start your nodes, you should see an entry similar to this in the logfile:

[INFO ][com.floragunn.searchguard.ssl.SearchGuardKeyStore] Open SSL OpenSSL 1.0.2d 9 Jul 2015 available
[INFO ][com.floragunn.searchguard.ssl.SearchGuardKeyStore] Open SSL available ciphers [ECDHE-RSA-AES256-GCM-SHA384,...

If you see one of those two error messages in the logfile, OpenSSL is not available and we fall back to JCE.

java.lang.ClassNotFoundException: org.apache.tomcat.jni.SSL

  • netty-tcnative jar is missing
  • make sure you use the netty-tcnative jar matching your platform, either _linux-x86_64.jar_ or _linux-x86_64-fedora.jar_ or _osx-x86_64.jar_ or _windows-x86_64.jar_


  • OpenSSL is not installed. See above.
  • Apache Portable Runtime (APR) is not installed. See above.
  • Make sure your /tmp directory is writeable and not mounted with noexec
  • If you run inside a docker container AUFS filesystem for /tmp can make trouble

Further reading

More about netty-tcnative can be found here.

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