Logstash JMX input plugin cannot load Cassandra configuration

Elastic Stack Logstash
1

I am trying to get Cassandra metrics through logstash jmx input. My logstash pipeline conf:

/etc/logstash/conf.d/cassandra_jmx.conf
input {
   jmx {
      path => "/etc/logstash/jmxconf"
      polling_frequency => 15
      type => "jmx"
      nb_thread => 4
   }
}

output {
 elasticsearch {
        hosts => ["<elastic_ip>:9200"]
        user  => "myuser"
        password => "mypass"
        }
}

/etc/logstash/jmxconf/jmx_config.json :

{
      "host" : "my-cassandra-node",
      "port" : 7199,
      "username" : "my_jmx_user",
      "password": "my_jmx_pass",
      "alias" : "test.homeserver.elasticsearch",
"queries" : [{
     "object_name" : "org.apache.cassandra.metrics:type=ThreadPools,path=request,scope=RequestResponseStage,name=*",
     "object_alias" : "${type}.${path}.${scope}.${name}"
}, {
    "object_name" : "java.lang:type=Threading",
    "object_alias" : "Threading"
  }, {
    "object_name" : "java.lang:type=Runtime",
    "attributes" : [ "Uptime", "StartTime" ],
    "object_alias" : "Runtime"
  }]
}

Logstash logs:

[2021-11-16T10:21:44,964][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:21:59,974][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:22:14,984][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:22:30,000][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:22:45,012][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:23:00,026][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:23:15,037][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:23:30,077][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:23:45,087][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:24:00,099][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:24:15,109][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:24:30,119][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:24:45,135][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:25:00,149][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:25:15,160][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:25:30,172][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:25:45,184][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:26:00,196][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
[2021-11-16T10:26:15,205][INFO ][logstash.inputs.jmx      ][main][70c0319670d071bebf194cd4cefe30e2af3a41403e29630d54efa022132d965f] Loading configuration files in path {:path=>"/etc/logstash/jmxconf"}
2

What is your question?

3

The question is why this info logs continue indefinitely?

4

The main run function sits in a loop loading the configuration, logging this message, and calling thread_jmx. The thread_jmx function also loops. If you enable log.level debug it should be a lot easier to determine what path the code is taking.

5

I think you can use Jolokia to extract the metrics of Cassandra to the Rest API and run the metricbeat agent with enable jolokia module.