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conduktor / kafka-stack-docker-compose

docker compose files to create a fully working kafka stack
Apache License 2.0
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Hosts file changes #10

Closed cojack closed 7 years ago

cojack commented 7 years ago

@simplesteph could you explain to me why do I have to change hosts file on machine where I run app that connect to kafka? I guess it's only required for HOST where kafka is running.

simplesteph commented 7 years ago

Hi @cojack Kafka has a concept of advertised host, and when you talk to kafka, it will ask you to communicate using the advertised host (all of that is done by the client). So as I set the advertised host to kafka1 for the first broker, when your programs connect to kafka1, they actually need to know that is also means localhost, hence the /etc/hosts file changes. Makes sense?

It's also very much due to how docker handles networking, as every machine inherits a hostname and knows about each other within their network, but not the host machine

cojack commented 7 years ago

@simplesteph nope I does not explain me anything xD But don't worry, I don't have to know everything, just figured out that npm package no-kafka allows me to redirect brokers so I just map kafka{N} to correct host without touching the /etc/hosts files. Thanks a lot for your work with this easy docker kafka setup!