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Yep, "no route to host"!! After double-checking that these two AWS hosts should be able to talk to each other on these ports it seemed logical that the box's firewall might be "helping" me out. I quickly found out that with CentOS 7, we've moved away from iptables and to firewalld. Thankfully, man firewall-cmd was there to help me out. I just needed to add these two ports and the following commands shows show what the configuration looked like before and after I made these mods.
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More importantly, I could not connect to this novel Kafka configuration of Kafka I was using for some testing.
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