It’s occasionally useful to test a Kafka connection; for example in case you want to verify that your security groups are properly configured. Kafka speaks a binary protocol so cURL is out. It also ships with very heavy tools that are difficult to install, and so those may not be suitable in many cases either.
Luckily, a basic telnet session makes a pretty reasonable test:
$ telnet kafka.brandur.org 9092
Trying 10.100.15.15...
Connected to kafka.brandur.org.
Escape character is '^]'.
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