Logstash logs are read but are not pushed to elasticsearch

[ghimisradu]

I have the following logstash configuration:

logstash-configration.conf

input {
  file {
	codec => "json_lines"
	path => ["/etc/logstash/input.log"]
	sincedb_path => "/etc/logstash/dbfile"
	start_position => "beginning"
	ignore_older => "0"
  }
}
output {
   elasticsearch {
      hosts => ["192.168.169.46:9200"]
   }
   stdout {
      codec => rubydebug
   }
}

The /etc/logstash/input.log file is populated with logs from a running java application. The logs are in the following json format (they are written inline separated by the \n character):

log-input-formatted

{
"exception": {
	"exception_class": "java.lang.RuntimeException",
	"exception_message": "Test runtime exception stack: 0",
	"stacktrace": "java.lang.RuntimeException: Test runtime exception stack: 0"
},
"@version": 1,
"source_host": "WS-169-046",
"message": "Test runtime exception stack: 0",
"thread_name": "parallel-1",
"@timestamp": "2019-12-02T16:30:14.084+02:00",
"level": "ERROR",
"logger_name": "nl.hnf.logs.aggregator.demo.LoggingTest",
"aplication-name": "demo-log-aggregation"
}

I also updated the logstash default template using the elasticsearch API:

Put request body at: http://192.168.169.46:9200/_template/logstash?pretty

{
"index_patterns": "logstash-*",
"version": 60002,
"settings": {
    "index.refresh_interval": "5s",
    "number_of_shards": 1
},
"mappings": {
    "dynamic_templates": [
        {
            "message_field": {
                "path_match": "message",
                "match_mapping_type": "string",
                "mapping": {
                    "type": "text",
                    "norms": false
                }
            }
        },
        {
            "string_fields": {
                "match": "*",
                "match_mapping_type": "string",
                "mapping": {
                    "type": "text",
                    "norms": false,
                    "fields": {
                        "keyword": {
                            "type": "keyword",
                            "ignore_above": 256
                        }
                    }
                }
            }
        }
    ],
    "properties": {
        "@timestamp": {
            "type": "date"
        },
        "@version": {
            "type": "keyword"
        },
        "source_host": {
            "type": "keyword"
        },
        "message": {
            "type": "text"
        },
        "thread_name": {
            "type": "text"
        },
        "level": {
            "type": "keyword"
        },
        "logger_name": {
            "type": "keyword"
        },
        "aplication_name": {
            "type": "keyword"
        },
        "exception": {
            "dynamic": true,
            "properties": {
                "exception_class": {
                    "type": "text"
                },
                "exception_message": {
                    "type": "text"
                },
                "stacktrace": {
                    "type": "text"
                }
            }
        }
    }
}

}

Elasticsearch responds with "acknowledged": true and I can see the template being updated via API.

Now starting logstash with debug log level i see the input logs being read but not sent to elasticsearch, although the index is created but it's always empty:

[2019-12-03T09:30:51,655][DEBUG][logstash.inputs.file     ][custom] Received line {:path=>"/etc/logstash/input.log", :text=>"{\"@version\":1,\"source_host\":\"ubuntu\",\"message\":\"Generating some logs: 65778 - 2019-12-03T09:30:50.775\",\"thread_name\":\"parallel-1\",\"@timestamp\":\"2019-12-03T09:30:50.775+00:00\",\"level\":\"INFO\",\"logger_name\":\"nl.hnf.logs.aggregator.demo.LoggingTest\",\"aplication-name\":\"demo-log-aggregation\"}"}
[2019-12-03T09:30:51,656][DEBUG][filewatch.sincedbcollection][custom] writing sincedb (delta since last write = 1575365451)

Output of http://192.168.169.46:9200/_cat/indices?v call:
health | status | index |uuid |pri | rep | docs.count | docs.deleted | store.size | pri.store.size
green | open | logstash-2019.12.03-000001| ADb37pLARoWJQah5RFFuuA |1|0|0|0|283b| 283b

As you can see the index is created but the docs.count is always 0 and no data is pushed to elasticsearch.

Also, the elasticsearch logs are on debug level too, but i don't see any errors there or anything that could give me a hint about the source of the problem.

Do you guys have any idea or suggestion on why the logs are not pushed to elasticsearch?

[mathur7vidit (vidit mathur)]

can you share your logstash configuration for further analysis

[ghimisradu]

Check the second line of the post

[ghimisradu]

It seems that the json_lines codec is not compatible with file input(documentation is not very accurate on this)
fixed the issue by using:

input {
  file {
	codec => "json"
	path => ["/etc/logstash/input.log"]
  }
}
output {
   elasticsearch {
  hosts => ["192.168.169.46:9200"]
   }
   stdout {
  codec => rubydebug
   }
}