Error, cannot retrieve cgroups information undefined method `[]' for nil:NilClass

[ypkkhatri (Yougeshwar Khatri)]

Hi,

I'm using logstash to import csv to elasticsearch with specific config file using this command logstash-6.3.2/bin/logstash -f my_logstash.config --debug but throwing below error:

[2018-08-16T11:20:05,083][DEBUG][logstash.instrument.periodicpoller.cgroup] Error, cannot retrieve cgroups information {:exception=>"NoMethodError", :message=>"undefined method `[]' for nil:NilClass"}
[2018-08-16T11:20:05,228][DEBUG][logstash.instrument.periodicpoller.jvm] collector name {:name=>"ParNew"}
[2018-08-16T11:20:05,231][DEBUG][logstash.instrument.periodicpoller.jvm] collector name {:name=>"ConcurrentMarkSweep"}
[2018-08-16T11:20:06,259][DEBUG][logstash.pipeline        ] Pushing flush onto pipeline {:pipeline_id=>"main", :thread=>"#<Thread:0x262044dd sleep>"}

My logstash config file:

input {
    file {
        path => "/home/testuser/data/my-data.csv"
        start_position => "beginning"
        sincedb_path => "/dev/null"
    }
}
filter {
    csv {
        separator => ","
        columns => ["id","created","status"]
    }
    if ([id] == "id") {
        drop {}
    }
    uuid {
        target => "id"
        overwrite => true
    }
    if [status] == "NULL" {
        mutate {remove_field => ["status"]}
    } else {
        mutate {convert => ["status", "integer"]}
    }
    if [created] == "NULL" {
        mutate {remove_field => ["created"]}
    } else {
        date {
            locale => "de"
            match => [ "created", "yyyy-MM-dd HH:mm:ss" ]
            target => "created"
            timezone => "Europe/Berlin"
        }
    }
}

output {
    elasticsearch {
        hosts => "http://localhost:9200"
        index => "my_index"
        document_type => "doc"
    }
    stdout {}
}

That index my_index is already exists.

Please help, I'm using Ubuntu 18.04 LTS

Thank you