logstash-2.1.conf

input {
  stdin {
    type => "stdin-type"
  }

  file {
    type => "syslog"
    path => [ "/var/log/*.log", "/var/log/messages", "/var/log/syslog" ]
  }

  file {
    type => "logstash"
    path => [ "/var/log/logstash/logstash.log" ]
    start_position => "beginning"
  }
}

filter {
  if [type] == "docker" {
    json {
      source => "message"
    }
    mutate {
      rename => [ "log", "message" ]
    }
    date {
      match => [ "time", "ISO8601" ]
    }
  }
}

output {
  elasticsearch {
    hosts => "ELASTICSEARCH_HOST:ELASTICSEARCH_PORT"
  }
}