Graylog unable to receive message from logstash

Graylog Add-ons
4

Thank you Jan and jochen for replying. Yes, the correct input is GELF UDP.

Below is my logstash configurations that make it worked.

input {
  jdbc {
    jdbc_driver_library => "/logstash-6.3.0/lib/sqljdbc42.jar"
    jdbc_driver_class => "com.microsoft.sqlserver.jdbc.SQLServerDriver"
    jdbc_connection_string => "jdbc:sqlserver://XXX:XXX;databaseName=XXX"
    jdbc_user => "XXX"
    jdbc_password => "XXX"
    schedule => "* * * * *"
    statement => "select xxx from XXX"
  }
}

filter {
 mutate {
   add_field => { "message" => "Test server" }
   add_field => { "host" => "graylog_server" }
 }
}


output {
  gelf {
  host => "graylog_ip_address"
  port => 12201
  short_message => "Testing gelf output"
  }
  stdout { codec => rubydebug }
}

Below is my GELF UDP INPUT setting.

GELF UDP : running
bind_address: graylog_server
decompress_size_limit: 8388608
override_source: <empty>
port: 12201
recv_buffer_size: 262144

Thank you.