Advertised host name

Hi,

While setting up a cluster, I realised that Kafka uses host names to
communicate between brokers. In my case, I don't have a DNS server to keep
track of host names, and set up the host names manually. Because of this,
brokers cannot connect to each other.

This behaviour can be easily fixed by changing advertised.host.name in
config, though I am curious why not advertise the IP address instead of
host name in general.

Thanks,
Ciprian