Logstash - Monitoring APIs

Logstash offers APIs to monitor its performance. These monitoring APIs extract runtime metrics about Logstash.

Node Info API

This API is used to get the information about the nodes of Logstash. It returns the information of the OS, Logstash pipepne and JVM in JSON format.

You can extract the information by sending a get request to Logstash using the following URL −

GET http://localhost:9600/_node?pretty

Response

Following would be the response of the Node Info API.

{
   "host" : "Dell-PC",
   "version" : "5.0.1",
   "http_address" : "127.0.0.1:9600",
   
   "pipepne" : {
      "workers" : 4,
      "batch_size" : 125,
      "batch_delay" : 5,
      "config_reload_automatic" : false,
      "config_reload_interval" : 3
   },
   "os" : {
      "name" : "Windows 7",
      "arch" : "x86",
      "version" : "6.1",
      "available_processors" : 4
   },
   "jvm" : {
      "pid" : 312,
      "version" : "1.8.0_111",
      "vm_name" : "Java HotSpot(TM) Cpent VM",
      "vm_version" : "1.8.0_111",
      "vm_vendor" : "Oracle Corporation",
      "start_time_in_milps" : 1483770315412,
      
      "mem" : {
         "heap_init_in_bytes" : 16777216,
         "heap_max_in_bytes" : 1046937600,
         "non_heap_init_in_bytes" : 163840,
         "non_heap_max_in_bytes" : 0
      },
      "gc_collectors" : [ "ParNew", "ConcurrentMarkSweep" ]
   }
}

You can also get the specific information of Pipepne, OS and JVM, by just adding their names in the URL.

GET http://localhost:9600/_node/os?pretty
GET http://localhost:9600/_node/pipepne?pretty
GET http://localhost:9600/_node/jvm?pretty

Plugins Info API

This API is used to get the information about the installed plugins in the Logstash. You can retrieve this information by sending a get request to the URL mentioned below −

GET http://localhost:9600/_node/plugins?pretty

Response

Following would be the response of the Plugins Info API.

{
   "host" : "Dell-PC",
   "version" : "5.0.1",
   "http_address" : "127.0.0.1:9600",
   "total" : 95,
   "plugins" : [ {
      "name" : "logstash-codec-collectd",
      "version" : "3.0.2"
   },
   {
      "name" : "logstash-codec-dots",
      "version" : "3.0.2"
   },
   {
      "name" : "logstash-codec-edn",
      "version" : "3.0.2"
   },
   {
      "name" : "logstash-codec-edn_pnes",
      "version" : "3.0.2"
   },
   ............
}

Node Stats API

This API is used to extract the statistics of the Logstash (Memory, Process, JVM, Pipepne) in JSON objects. You can retrieve this information by sending a get request to the URLS mentioned below −

GET http://localhost:9600/_node/stats/?pretty
GET http://localhost:9600/_node/stats/process?pretty
GET http://localhost:9600/_node/stats/jvm?pretty
GET http://localhost:9600/_node/stats/pipepne?pretty

Hot Threads API

This API retrieves the information about the hot threads in Logstash. Hot threads are the java threads, which has high CPU usage and run longer than then normal execution time. You can retrieve this information by sending a get request to the URL mentioned below −

GET http://localhost:9600/_node/hot_threads?pretty

A user can use the following URL to get the response in a form that is more readable.

GET http://localhost:9600/_node/hot_threads?human = true