We have a kafka broker setup on internal cloud. We find actual url using zookeeper and provide in bootstrap.server config.
Now the problem is when the broker restarts the internal cloud restarts it on dynamically allotted machine with new host port. Now the host port which i have initially given in producer config is not valid.
Question is how can i reload this config without restart.
Note: i know this is a bad design to host broker where it can restart in a different machine, but this is how it is right now.
I think you can use the domain name instead of ip in bootstrap.server config.
Related
Able to connect successfully to local kafka broker/cluster running locally (dockerized) using Conduktor, but when trying to connect to Kafka cluster running on Unix VM, getting below error.
Error:
"The broker [...] is reachable but Kafka can't connect. Ensure you have access to the advertised listeners of the the brokers and the proper authorization"
Appreciate any assistance.
running locally (dockerized)
When running in docker, you need to ensure that the ports are accessible from outside of your container. To verify this, try doing a telnet <ip> <port> and check if you are able to connect.
Since the error message says, the broker is reachable, I suppose you would be able to successfully telnet to the broker.
Next, check your broker config called advertised.listeners. Here you need to mention your IP:Port combination where IP is what you will be giving in your client program i.e. Conduktor.
An example for that would be
advertised.listeners=PLAINTEXT://1.2.3.4:9092
and then restart your broker and reconnect. If you are using ssl then you need to provide some extra configuration. See Configuring Kafka brokers for more.
Try to add in /etc/hosts (Unix-like) or C:\Windows\System32\drivers\etc\hosts (windows-like) the Kafka server in such manner kafka_server_ip kafka_server_name_in_dns (e.g. 10.10.0.1 kafka).
In a PoC cloudera cluster provided with kafka(1 broker) I'm trying to send messages to the cluster with an external producer through a public IP. My cluster nodes are hosted in Azure and all of them are reachable from my local machine where the external producer is running.
Following this great article https://rmoff.net/2018/08/02/kafka-listeners-explained/ I figured out the kafka listeners config I need as this broker public IP is only reachable from my local machine and inside the cluster they can only communicate using their internal hostnames:
listeners=INTERNAL://0.0.0.0:19092,EXTERNAL://0.0.0.0:9092
listener.security.protocol.map=INTERNAL:PLAINTEXT,EXTERNAL:PLAINTEXT
advertised.listeners=INTERNAL://internal-broker-node-hostname:19092,EXTERNAL://public-broker-ip:9092
inter.broker.listener.name=INTERNAL
With this configuration when I try to start the broker I get this error:
org.apache.kafka.common.config.ConfigException: Only one of inter.broker.listener.name and security.inter.broker.protocol should be set.
Which makes sense as in Kafka doc for this property inter.broker.listener.name they say:
Name of listener used for communication between brokers. If this is unset, the listener name is defined by security.inter.broker.protocol. It is an error to set this and security.inter.broker.protocol properties at the same time.
The problem I'm facing is that I'm unable to unset security.inter.broker.protocol through the cloudera manager as I only have the option of switching options in a radio button.
How can I unset that property?
Internal and external are just strings
So, you could set PLAINTEXT for CDH and just redefine the external listener as being advertised
listeners=PLAINTEXT://0.0.0.0:19092,EXTERNAL://0.0.0.0:9092
listener.security.protocol.map=EXTERNAL:PLAINTEXT,PLAINTEXT:PLAINTEXT
advertised.listeners=PLAINTEXT://internal-broker-node-hostname:19092,EXTERNAL://public-broker-ip:9092
You'll also want to make sure your external broker IPs are static
I've started learning some big data tools for a new project, and right now I'm on Kafka and Zookeeper.
I have them both install on my local machine, and I can start them up and start producing and consuming messages just fine. Now, I want to try it having two machines, one with a kafka broker, zookeepr and a producer, and the other with a consumer. Lets call them Machine A and Machine B.
Machine A has runs the Zookeeper server, the broker and a producer. Machine B runs a consumer. From what I think I understand, I should be able to setup the consumer to listen to a topic from the producer on Machine A, using Zookeeper. Since both machines are on the same network (i.e. my local home network), I thought I could change the kafka broker server.properties to use my static ip address for Machine A, and then have the consumer on Machine B connect to it.
My problem, is that zookeeper keeps spinning up on localhost, and connecting to 0.0.0.0/0.0.0.0:2181 so when my broker tries to connect to it using my static ip address (i.e 192.168.x.x), it times out. I have looked all over for a solution, but I cannot find anything that tells me how to configure the Zookeeper sever to start on a different ip address.
Maybe my understanding of these technologies is simply wrong, but I thought this would be a fairly simple thing to do. Does anyone know any way to resolve this? Or else if I'm doing it completely wrong, what is the correct approach
zookeeper keeps spinning up on localhost, and connecting to 0.0.0.0/0.0.0.0:2181
Well, that is the bind address.
You need to also (preferably) have a static IP for Zookeeper, then set zookeeper.connect within the server.properties file of Kafka to reach to that other machine's external address.
From the Zookeeper configuration file, you would make sure you have the myid file and have a line in the property file that looks like this (without the double brackets)
server.{{ myid }}={{ ip_address }}:2888:3888
You wouldn't find this in the Kafka documentation, but it is in the Zookeeper documentation
However, if Kafka and Zookeeper are on the same machine, this isn't necessary.
Your external consumer should be setting bootstrap.servers property and the Kafka IP address(es) w/ port 9092.
Your problem might me related instead to the advertised.listeners setting within Kafka.
For example, start with listeners=PLAINTEXT://:9092
As of Zookeeper 3.3.0 (see Advanced Configuration):
clientPortAddress : New in 3.3.0: the address (ipv4, ipv6 or hostname)
to listen for client connections; that is, the address that clients
attempt to connect to. This is optional, by default we bind in such a
way that any connection to the clientPort for any
address/interface/nic on the server will be accepted
So you could use:
clientPortAddress=127.0.0.1
I am facing below error message when i was trying to connect and see the topic/consumer details of one of my kafka clusters we have.
we have 3 brokers in the cluster which I able to see but the topic and its partitions.
Note : I have kafka 1.0 and kafka tool version is 2.0.1
I had the same issue on my MacBook Pro. The tool was using "tshepo-mbp" as the hostname which it could not resolve. To get it to work I added 127.0.0.1 tshepo-mbp to the /etc/hosts file.
kafka tool is most likely using the hostname to connect to the broker and cannot reach it. You maybe connecting to the zookeeper host by IP address but make sure you can connect/ping the host name of the broker from the machine running the kafka tool.
If you cannot ping the broker either fix the network issues or as a workaround edit the host file on your client to let it know how to reach the broker by its name
This issue occurs if you have not set listeners and advertised.listeners property in server.properties file.
For Ex:
config/server.properties
...
listeners=PLAINTEXT://:9092
...
advertised.listeners=PLAINTEXT://<public-ip/host-name>:9092
...
To fix this issue, we need to change the server.properties file.
$ vim /usr/local/etc/kafka/server.properties
Here update the listeners value from
listeners=PLAINTEXT://:9092
to
listeners=PLAINTEXT://localhost:9092
source:https://medium.com/#Ankitthakur/apache-kafka-installation-on-mac-using-homebrew-a367cdefd273
For better visibility (even already commented the same in early days thread)
In my case, I got to know when I used Kafkatool from my local machine, tool tris to find out Kafka broker port which was blocked from my cluster admins for my local machine, that is the reason I was not able to connect.
Resolution:
Either ask the admin to open the port for intranet if they can, if they can not you can use tunnelling for your testing purpose or time being for your port.
Hope this would help a few.
In our Openshift ecosystem, we have a kafka instance sourced from wurstmeister/kafka. As of now I am able to have the kafka accessible withing the Openshift system using the below parameters,
KAFKA_LISTENERS=PLAINTEXT://:9092
KAFKA_ADVERTISED_HOST_NAME=kafka_service_name
And ofcourse, the params for port and zookeper is there.
I am able to access the kafka from the pods within the openshift system. But I am unable to access kafka service from the host machine. Eventhough I am able to access the kafka pod using its IP and able to telnet the pod using, telnet Pod_IP 9092
When I am trying to connect using the kafka producer from the host machine, I am getting the below error,
2017-08-07 07:45:13,925] WARN Error while fetching metadata with
correlation id 2 : {tls21=LEADER_NOT_AVAILABLE}
(org.apache.kafka.clients.NetworkClient)
And When I try to connect from Kafka consumer from the host machine using IP, it is blank.
Note: As of now, its a single openshift server. And the use case is for dev testing.
Maybe you want to take a look at this POC for having Kafka on OpenShift ?
https://github.com/EnMasseProject/barnabas