Can’t get Logstash to read existing Kafka topic from start - apache-kafka

I'm trying to consume a Kafka topic using Logstash, for indexing by Elasticsearch. The Kafka events are JSON documents.
We recently upgraded our Elastic Stack to 5.1.2.
I believe that I was able to consume the topic OK in 5.0, using the same settings, but that was a while ago so perhaps I'm doing something wrong now, but can't see it. This is my config (slightly sanitized):
input {
kafka {
bootstrap_servers => "host1:9092,host2:9092,host3:9092"
client_id => "logstash-elastic-5-c5"
group_id => "logstash-elastic-5-g5"
topics => "trp_v1"
auto_offset_reset => "earliest"
}
}
filter {
json {
source => "message"
}
mutate {
rename => { "#timestamp" => "indexedDatetime" }
remove_field => [
"#timestamp",
"#version",
"message"
]
}
}
output {
stdout { codec => rubydebug }
elasticsearch {
hosts => ["host10:9200", "host11:9200", "host12:9200", "host13:9200"]
action => "index"
index => "trp-i"
document_type => "event"
}
}
When I run this, no messages are consumed, no sign of activity appears in the log after "[org.apache.kafka.clients.consumer.internals.ConsumerCoordinator] Setting newly assigned partitions", and in Kafka Manager the consumer appears to immediately appear with "total lag = 0" for the topic.
This version of the Kafka plugin stores consumer offsets in Kafka itself, so each time I try to run Logstash against the same topic, I increment the group_id so in theory, it should start from the earliest offset for the topic.
Any advice?
EDIT: It appears that despite setting auto_offset_reset to "earliest", it isn't working - it's as if it's being set to "latest". I left Logstash running, then had more entries loaded into the Kafka queue, and they were processed by Logstash.

Related

Unable to send message to kafka Producer using kafka-node

I am using default server.properties/zookeeper.properties files provided by Kafka framework.
I am trying to create a simple NodeJS app which would send messages to Producer and consume them.
Below is NodeJS code.
config.js
module.exports = {
kafka_topic: 'catalog',
kafka_server: 'localhost:9092',
};
nodejs-producer.js
const kafka = require('kafka-node');
const config = require('./config');
try {
// set the desired timeout in options
const options = {
timeout: 5000,
};
const Producer = kafka.Producer;
const client = new kafka.KafkaClient({kafkaHost: config.kafka_server, requestTimeout: 5000});
const producer = new Producer(client);
const kafka_topic = config.kafka_topic;
let payloads = [
{
topic: kafka_topic,
messages: 'This is test message'
}
];
producer.on('ready', async function() {
let push_status = producer.send(payloads, (err, data) => {
if (err) {
console.log(err.toString());
console.log('[kafka-producer -> '+kafka_topic+']: broker update failed');
} else {
console.log(data.toString());
console.log('[kafka-producer -> '+kafka_topic+']: broker update success');
}
});
});
producer.on('error', function(err) {
console.log(err);
console.log('[kafka-producer -> '+kafka_topic+']: connection errored');
throw err;
});
}
catch(e) {
console.log(e);
}
kafka version = 2.8.0
kafka-node version = 5.0.0
I am getting the error - Error: LeaderNotAvailable
How to fix this? I tried playing with different values in server.properties file like advertised.listeners but didn't get solution.
I have already answered this problem here
In short: this problem happens when trying to produce messages to a topic that doesn't exist.
You may configure your kafka installation to automatically create topic in such case: what will then happen is - in order: you will still receive the error message and the framework will create the topic. In my case i then had to re-produce the same message a second time but this was on an old version of Kafka.
EDIT:
here a link to a post which explains how to setup your kafka configuration to automatically create kafka topics.
I have also faced same issue while sending a message. I solved the issue by adding a partition in the payload and same partition is used in the consumer also.
Code I have used
Since I got this error in the development environment. I solved this problem by deleting the zookeeper snapshot and Kafka consumer offset.
NOTE: Don't do this on production.
rm -rf /tmp/zookeeper
rm -rf /tmp/kafka-logs

Can logstash's Google Cloud Storage output plugin do persistent transmission after restart machine?

Using this config for logstash's output. It's using /tmp/logstash-gcs as a local folder. Send to GCS when file become 1024 kbytes.
input {
beats {
port => 5044
}
}
filter {}
output {
google_cloud_storage {
bucket => "gcs-bucket-name"
json_key_file => "/secrets/service_account/credentials.json"
temp_directory => "/tmp/logstash-gcs"
log_file_prefix => "logstash_gcs"
max_file_size_kbytes => 1024
output_format => "json"
date_pattern => "%Y-%m-%dT%H:00"
flush_interval_secs => 2
gzip => false
gzip_content_encoding => false
uploader_interval_secs => 60
include_uuid => true
include_hostname => true
}
}
After restart machine, can it continuous do the job schedule without any data loss?
Does it has a queue feature to manage as pub/sub?
About solution, there are 2 ways.
Use filebeat to beat those tmp files again.
Set grace period seconds to insure logstash has enough time to send last task when machine down.

Logstash avro output cannot be decoded by apache avro-tools

I am a beginner with both Logstash and Avro.
We are setting up a system with logstash as producer for a kafka queue. However, we are running into the problem that the avro serialized events produced by Logstash cannot be decoded by the avro-tools jar (version 1.8.2) that apache provides. Furthermore, we notice that the serialized output by Logstash and avro-tools differs.
We have the following setup:
logstash version 5.5
logstash avro codec version 3.2.1
kafka version 0.10.1
avro-tools jar version 1.8.2
As example, consider the following schema:
{
"name" : "avroTestSchema",
"type" : "record",
"fields" : [ {
"name" : "testfield1",
"type" : "string"
},
{
"name" : "testfield2",
"type" : "string"
}
]
}
and the following json string:
{"testfield1":"somestring","testfield2":"anotherstring"}
When serializing using Logstash.
Logstash config file:
input {
stdin {
codec => json
}
}
filter {
mutate {
remove_field => ["#timestamp", "#version"]
}
}
output {
kafka {
bootstrap_servers => "localhost:9092"
codec => avro {
schema_uri => "/path/to/TestSchema.avsc"
}
topic_id => "avrotestout"
}
stdout {
codec => rubydebug
}
}
output (using cat):
FHNvbWVzdHJpbmcaYW5vdGhlcnN0cmluZw==
When serializing using avro-tools.
command:
java -jar avro-tools-1.8.2.jar jsontofrag --schema-file TestSchema.avsc message.json
output
somestringanotherstring
command:
java -jar avro-tools-1.8.2.jar fromjson --schema-file TestSchema.avsc message.json
output:
Objavro.codenullavro.schema▒{"type":"record","name":"avroTestSchema","fields":[{"name":"testfield1","type":"string"},{"name":"testfield2","type":"string"}]}▒▒▒▒&70▒▒Hs▒U2somestringanotherstring▒▒▒▒&70▒▒Hs▒U
So our question is:
How do we configure Logstash such that the output becomes compatible with the apache avro-tools jar?
UPDATE: We found out that the logstash produced avro output is base64 encoded. However cannot find where this happens, and how to make it avro-tools compatible
As mentioned in the update, we found out that the standard Logstash Avro codec adds a non optional base64 encoding to the avro output. We found this undesirable. So we forked the codec and made this encoding configurable. We tested this and it worked out of the box on several of our systems.
The fork is available on github: https://github.com/Rubyan/logstash-codec-avro
To set (or unset) the base64 encoding, add this to your logstash config file:
output {
stdout {
codec => avro {
schema_uri => "schema.avsc"
base64_encoding => false
}
}
}

Logstash not forwarding logs to ES via Kafka

I'm using ELK 5.0.1 and Kafka 0.10.1.0 . I'm not sure why my logs aren't forwarding I installed Kafkacat and was successfully able to Produce and Consume logs from all the 3 servers where Kafka cluster is installed.
shipper.conf
input {
file {
start_position => "beginning"
path => "/var/log/logstash/logstash-plain.log"
}
}
output {
kafka {
topic_id => "stash"
bootstrap_servers => "<i.p1>:9092,<i.p2>:9092,<i.p3>:9092"
}
}
receiver.conf
input {
kafka {
topics => ["stash"]
group_id => "stashlogs"
bootstrap_servers => "<i.p1>:2181,<i,p2>:2181,<i.p3>:2181"
}
}
output {
elasticsearch {
hosts => ["<eip>:9200","<eip>:9200","<eip>:9200"]
manage_template => false
index => "logstash-%{+YYYY.MM.dd}"
}
}
Logs: Getting the below warnings in logstash-plain.log
[2017-04-17T16:34:28,238][WARN ][org.apache.kafka.common.protocol.Errors] Unexpected error
code: 38.
[2017-04-17T16:34:28,238][WARN ][org.apache.kafka.clients.NetworkClient] Error while fetching
metadata with correlation id 44 : {stash=UNKNOWN}
It looks like your bootstrap servers are using zookeeper ports. Try using Kafka ports (default 9092)

Reading from multiple topics in Apache Kafka

I'm trying to read from multiple kafka topics (say 'newtest-1' and 'newtest-2') using 'white_list' configuration in the logstash input plugin. My logstash conf looks like:
input { kafka { white_list => "newtest-1|newtest-2" } } output { stdout {codec => rubydebug } }
With this configuration I can successfully read from two different topics. But I want to use regex for input topics as I'm expecting the topics to be of the form 'newtest-*'. According to the suggestion in this link, the following configuration should work:
input { kafka { white_list => "newtest-*" } } output { stdout {codec => rubydebug } }
But with this I'm not able to read from kafka. Any help is appreciated.
The white_list should be newtest-.*
This is relevant to older versions of the plugin. Now you can use topics.