I have been struggling to get xpack working with logstash. When disabled it works.
logstash version is 6.2.3.
error i see is:
[2018-03-31T22:02:18,031][INFO ][logstash.modules.scaffold] Initializing module {:module_name=>"netflow", :directory=>"/usr/share/logstash/modules/netflow/configuration"}
[2018-03-31T22:02:18,042][FATAL][logstash.runner ] An unexpected error occurred! {:error=>#<ArgumentError: Setting "xpack.monitoring.enabled" hasn't been registered>, :backtrace=>["/usr/share/logstash/logstash-core/lib/logstash/settings.rb:37:in `get_setting'", "/usr/share/logstash/logstash-core/lib/logstash/settings.rb:70:in `set_value'", "/usr/share/logstash/logstash-core/lib/logstash/settings.rb:89:in `block in merge'", "org/jruby/RubyHash.java:1343:in `each'", "/usr/share/logstash/logstash-core/lib/logstash/settings.rb:89:in `merge'", "/usr/share/logstash/logstash-core/lib/logstash/settings.rb:138:in `validate_all'", "/usr/share/logstash/logstash-core/lib/logstash/runner.rb:264:in `execute'", "/usr/share/logstash/vendor/bundle/jruby/2.3.0/gems/clamp-0.6.5/lib/clamp/command.rb:67:in `run'", "/usr/share/logstash/logstash-core/lib/logstash/runner.rb:219:in `run'", "/usr/share/logstash/vendor/bundle/jruby/2.3.0/gems/clamp-0.6.5/lib/clamp/command.rb:132:in `run'", "/usr/share/logstash/lib/bootstrap/environment.rb:67:in `<main>'"]}
[2018-03-31T22:02:18,045][ERROR][org.logstash.Logstash ] java.lang.IllegalStateException: org.jruby.exceptions.RaiseException: (SystemExit) exit
Verified x-pack is installed.
/logstash-plugin list | grep x-pack
x-pack