I have set up a AWS EC2 instance running Apache Kafka 0.8 via a Bitnami AMI image. The server properties are pretty much default (Kafka located at localhost:9092 and zookeeper located at localhost:2181).
When I SSH into the machine, I can produce/consume data using the scripts provided by Kafka, located at kafka/bin.
To produce I run the following command:
./kafka-console-producer.sh --broker-list localhost:9092 --topic test
To Consume:
./kafka-console-consumer.sh --zookeeper localhost:2181 --topic test --from-beginning
This works correctly, thus I have determined that Kafka is functioning correctly. Next I attempted to produce/consume from my machine, using the python library pykafka:
client = KafkaClient(hosts = KAFKA_HOST)
topic = client.topics[sys.argv[1]]
try:
with topic.get_producer(max_queued_messages=1, auto_start=True) as producer:
while True:
for i in range(10):
message = "Test message sent on: " + str(datetime.datetime.now().strftime("%I:%M%p on %B %d, %Y"))
encoded_message = message.encode("utf-8")
mess = producer.produce(encoded_message)
except Exception as error:
print('Something went wrong; printing exception:')
print(error)
And I consume as follows:
client = KafkaClient(hosts = KAFKA_HOST)
topic = client.topics[sys.argv[1]]
try:
while True:
consumer = topic.get_simple_consumer(auto_start=True)
for message in consumer:
if message is not None:
print (message.offset, message.value)
except Exception as error:
print('Something went wrong; printing exception:')
print(error)
These snippets run without errors or exceptions, but no messages are produced or consumed, not even the ones created via the local scripts.
I have confirmed that both ports 9092 and 2181 are open via telnet.
My questions are as follows:
Is there a way to debug such problems and find the root cause? I would expect the library to throw an exception if there is some connectivity issues.
What is going on?
Related
Trying to send message from my local to remote Kafka
server.properties file:-
listeners=PLAINTEXT://0.0.0.0:9092
advertised.listeners=PLAINTEXT://<PUBLIC_IP>:9092
Tried to produce using the command
./bin/kafka-console-producer.sh --broker-list <PUBLIC_IP>:9092 --topic first_topic
Tried to consume using the command
./bin/kafka-console-consumer.sh --bootstrap-server <PUBLIC_IP>:9092 --topic first_topic --from-beginning
Getting the following error while producing
org.apache.kafka.common.KafkaException: Producer closed while send in progress
at org.apache.kafka.clients.producer.KafkaProducer.doSend(KafkaProducer.java:894)
at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:870)
at kafka.tools.ConsoleProducer$.send(ConsoleProducer.scala:71)
at kafka.tools.ConsoleProducer$.main(ConsoleProducer.scala:53)
at kafka.tools.ConsoleProducer.main(ConsoleProducer.scala)
Caused by: org.apache.kafka.common.KafkaException: Requested metadata update after close
at org.apache.kafka.clients.producer.internals.ProducerMetadata.awaitUpdate(ProducerMetadata.java:126)
at org.apache.kafka.clients.producer.KafkaProducer.waitOnMetadata(KafkaProducer.java:1032)
at org.apache.kafka.clients.producer.KafkaProducer.doSend(KafkaProducer.java:891)
... 4 more
What else should be configured to produce to Kafka hosted in remote server. I have also opened the port 9092 and there is no authorization/authentication enabled.
The problem seems to be with Azure. Solved by changing the server.properties file with the following configuration:-
listener.security.protocol.map=INTERNAL:PLAINTEXT,EXTERNAL:PLAINTEXT
advertised.listeners=INTERNAL://:19092,EXTERNAL://<public_ip>:9092
listeners=INTERNAL://:19092,EXTERNAL://<public_ip>:9092
i'm trying to start a consumer using Apache Kafka, it used to work well, but i had to format my pc and reinstall everything again, and now when trying to run this:
bin/kafka-console-consumer.sh --bootstrap-server localhost:9092 --topic test --from-beginning
this is what i'm getting:
Missing required argument "[zookeeper]"
Option Description
------ -----------
--blacklist <blacklist> Blacklist of topics to exclude from
consumption.
--bootstrap-server <server to connect
to>
--consumer.config <config file> Consumer config properties file.
--csv-reporter-enabled If set, the CSV metrics reporter will
be enabled
--delete-consumer-offsets If specified, the consumer path in
zookeeper is deleted when starting up
--formatter <class> The name of a class to use for
formatting kafka messages for
display. (default: kafka.tools.
DefaultMessageFormatter)
--from-beginning If the consumer does not already have
an established offset to consume
from, start with the earliest
message present in the log rather
than the latest message.
--key-deserializer <deserializer for
key>
--max-messages <Integer: num_messages> The maximum number of messages to
consume before exiting. If not set,
consumption is continual.
--metrics-dir <metrics directory> If csv-reporter-enable is set, and
this parameter isset, the csv
metrics will be outputed here
--new-consumer Use the new consumer implementation.
--property <prop>
--skip-message-on-error If there is an error when processing a
message, skip it instead of halt.
--timeout-ms <Integer: timeout_ms> If specified, exit if no message is
available for consumption for the
specified interval.
--topic <topic> The topic id to consume on.
--value-deserializer <deserializer for
values>
--whitelist <whitelist> Whitelist of topics to include for
consumption.
--zookeeper <urls> REQUIRED: The connection string for
the zookeeper connection in the form
host:port. Multiple URLS can be
given to allow fail-over.
my guess is that there's some kind of problem with the zookeeper connection port, because it's telling me to specify the port which zookeeper has to use to get connected to kafka. I'm not sure of this though, and don't know how to figure out the port to specify if this was the problem. Any suggestions??
Thanks in advance for the help
It looks like you are using an old version of the Kafka tools that requires to set --new-consumer if you want to directly connect to the brokers.
I'd recommend picking a recent version of Kafka so you only need to specify --bootstrap-server like in your example: http://kafka.apache.org/downloads
I am running Kafka 0.10.0 on CDH 5.9, cluster is kerborized.
What I am trying to do is to write messages from a remote machine to my Kafka broker.
The cluster (where Kafka is installed) has internal as well as external IP addresses.
The machines' hostnames within the cluster get resolved to the private IPs, the remote machine resolves the same hostnames to the public IP addreses.
I opened the necessary port 9092 (I am using SASL_PLAINTEXT protocol) from remote machine to Kafka Broker, verified that using telnet.
First Step - in addition to the standard properties for the Kafka Broker, I configured the following:
listeners=SASL_PLAINTEXT://0.0.0.0:9092
advertised.listeners=SASL_PLAINTEXT://<hostname>:9092
I am able to start the console consumer with
kafka-console-consumer --new consumer --topic <topicname> --from-beginning --bootstrap-server <hostname>:9092 --consumer.config consumer.properties
I am able to use my custom producer from another machine within the cluster.
Relevant excerpt of producer properties:
security.protocol=SASL_PLAINTEXT
bootstrap.servers=<hostname>:9092
I am not able to use my custom producer from the remote machine:
Exception org.apache.kafka.common.errors.TimeoutException: Batch containing 1 record(s) expired due to timeout while requesting metadata from brokers for <topicname>-<partition>
using the same producer properties. I am able to telnet the Kafka Broker from the machine and /etc/hosts includes hostnames and public IPs.
Second Step - I modified server.properties:
listeners=SASL_PLAINTEXT://0.0.0.0:9092
advertised.listeners=SASL_PLAINTEXT://<kafkaBrokerInternalIP>:9092
consumer & producer within the same cluster still run fine (bootstrap
servers are now the internal IP with port 9092)
as expected remote producer fails (but that is obvious given that it
is not aware of the internal IP addresses)
Third Step - where it gets hairy :(
listeners=SASL_PLAINTEXT://0.0.0.0:9092
advertised.listeners=SASL_PLAINTEXT://<kafkaBrokerPublicIP>:9092
starting my consumer with
kafka-console-consumer --new-consumer --topic <topicname> --from-beginning --bootstrap-server <hostname>:9092 --consumer.config consumer.properties
gives me a warning, but I don't think this is right...
WARN clients.NetworkClient: Error while fetching metadata with correlation id 1 : {<topicname>=LEADER_NOT_AVAILABLE}
starting my consumer with
kafka-console-consumer --new-consumer --topic <topicname> --from-beginning --bootstrap-server <KafkaBrokerPublicIP>:9092 --consumer.config consumer.properties
just hangs after those log messages:
INFO utils.AppInfoParser: Kafka version : 0.10.0-kafka-2.1.0
INFO utils.AppInfoParser: Kafka commitId : unknown
seems like it cannot find a coordinator as in the normal flow this would be the next log:
INFO internals.AbstractCoordinator: Discovered coordinator <hostname>:9092 (id: <someNumber> rack: null) for group console-consumer-<someNumber>.
starting the producer on a cluster node with bootstrap.servers=:9092
I observe the same as with the producer:
WARN NetworkClient:600 - Error while fetching metadata with correlation id 0 : {<topicname>=LEADER_NOT_AVAILABLE}
starting the producer on a cluster node with bootstrap.servers=:9092 I get
org.apache.kafka.common.errors.TimeoutException: Failed to update metadata after 60000 ms.
starting the producer on my remote machine with either bootstrap.servers=:9092 or bootstrap.servers=:9092 I get
NetworkClient:600 - Error while fetching metadata with correlation id 0 : {<topicname>=LEADER_NOT_AVAILABLE}
I have been struggling for the past three days to get this to work, however I am out of ideas :/ My understanding is that advertised.hostnames serves for exactly this purpose, however either I am doing something wrong, or there is something wrong in the machine setup.
Any hints are very much appreciated!
I met this issue recently.
In my case , I enabled Kafka ACL, and after disable it by comment this 2 configuration, the problem worked around.
authorizer.class.name=kafka.security.auth.SimpleAclAuthorizer
super.users=User:kafka
And an thread may help you I think:
https://gist.github.com/jorisdevrede/a7933a99251452bb1867
What mentioned in it at the end:
If you only use a SASL_PLAINTEXT listener on the Kafka Broker, you
have to make sure that you have set the
security.inter.broker.protocol=SASL_PLAINTEXT too, otherwise you will
get a LEADER_NOT_AVAILABLE error in the client.
I have setup a multi node setup for kafka, everything seems to work well and show no error logs unless i try to push message to one producer. I get a message:
Bootstrap broker host2:2181 disconnected (org.apache.kafka.clients.NetworkClient)
and on the zookeeper logs i am getting:
"WARN Exception causing close of session 0x0 due to java.io.IOException:
Unreasonable length = 1701969920 (org.apache.zookeeper.server.NIOServerCnxn)"
i cleaned up my data directory which is "/var/zookeeper/data" still no luck.
Any help on the the would be much appriciated
Vaibhav looking at this line (Bootstrap broker host2:2181) looks like you are trying to connect to zookeeper instance rather than broker instance. By Default Kafka broker runs on 9092 port. So producer and consumer should be created as per below command
Producer :
bin/kafka-console-producer.sh --broker-list host1:9092,host2:9092 \
--topic "topic_name"
Consumer:
bin/kafka-console-consumer.sh --bootstrap-server <host_ip_of_producer>:9092 \
--topic "topic_name" --from-beginning
Setup
We have a 3 node kafka cluster, processing messages coming in through nginx. The nginx hands it off to a php which in turn forks a python process and calls the KafkaClient, SimpleProducer & Send_Message
The zookeeper is running on the same host as kafka, nginx is on a separate host. The ports 2181, 2182, 3888, 9092 are all open. No errors seen in starting zookeeper, kafka. All this setup is on AWS in the same vpc.
Kafka & Zookeeper is running as kafka user, Nginx is running as nginx, php-fpm running as apache
Versions
Kafka: 0.8.2
Python: 2.7.5
Relevant snippets from property files.
zookeeper.properties
dataDir=/data/zookeeper
clientPort=2181
maxClientCnxns=100
tickTime=2000
initLimit=5
syncLimit=2
server.1=172.31.41.78:2888:3888
server.2=172.31.45.245:2888:3888
server.3=172.31.23.101:2888:3888
producer.properties
metadata.broker.list=172.31.41.78:9092,172.31.45.245:9092,172.31.23.101:9092
consumer.properties
zookeeper.connect=172.31.41.78:2181,172.31.45.245:2181,172.31.23.101:2181
zookeeper.connection.timeout.ms=6000
server.properties (setup with appropriate IP on other machines)
port=9092
advertised.host.name=172.31.41.78
host.name=172.31.41.78
zookeeper.connect=172.31.41.78:2181,172.31.45.245:2181,172.31.23.101:2181
zookeeper.connection.timeout.ms=60000
php code
function sendDataToKafka($_data,$_srcType) {
try{
$pyKafka = "/usr/bin/python /etc/nginx/html/postMon.py ".$_srcType;
$dspec = array(
0 => array("pipe","r"),
1 => array("pipe","w"),
2 => array("file","/dev/null", "a")
);
$process = proc_open($pyKafka,$dspec,$pipes);
if (is_resource($process)) {
if(fwrite($pipes[0],$_data) == true){
fclose($pipes[0]);
echo stream_get_contents($pipes[1]);
fclose($pipes[1]);
proc_close($process);
echo "Process completed";
python code
import sys,json,time,ConfigParser
import traceback
sys.path.append("/etc/nginx/html/kafka_python-0.9.4-py2.7.egg")
from kafka import KafkaClient,SimpleProducer
try:
srcMap = {
'Alert' : 'alerts'
}
topic = srcMap.get(sys.argv[1],'events')
data = ''
data = 'Testing static Kafka message'
print 'Host: 172.31.23.101:9092'
kafka = KafkaClient("172.31.23.101:9092")
producer = SimpleProducer(kafka,random_start=True)
producer.send_messages(topic,data);
except Exception as e: # most generic exception you can catch
print str(e)
Scenarios
Scenario 1:
Running a
bin/kafka-console-producer.sh --zookeeper 172.31.41.78:2181,172.31.45.245:2181,172.31.23.101:2181 --topic alerts
on 1 shell
and
running
./kafka-console-consumer.sh --zookeeper 172.31.41.78:2181,172.31.45.245:2181,172.31.23.101:2181 --topic alerts
we are able to view messages
Scenario 2:
Running the python code command line (from the nginx host), able to view messages from the consumer
Scenario 3:
Running the php code command line (from nginx host), able to view messages from the consumer
Scenario 4:
Running from a REST client (as POSTMAN)/ CURL using the REST URL, get the following message:
<html>
<body>
Host: 172.31.23.101:9092
All servers failed to process request
<pre>Process completed</pre></body>
<html>
This shows, traffic going to nginx, nginx executing the php & python scripts, but erroring out when the first call to Kafka is made - KafkaClient happens. Somehow the python is unable to access Kafka.
Don't know if this is user permission/ silly config mistake.
Also......
We have a similar working setup in another vpc
The security groups, config files, codebase properties etc. are consistent
Upgrade options are not a possibility in near term
Any pointers/help/fresh pair of eyes would really help us going.
Thanks !
Finally figured the apache user did not have "right" permission.
selinuxconlist apache helped fix the issue.