I'm thinking about installing cassandra in two ec2 regions. There is at least one thing I don't understand. Documentation says
If using this snitch, you must configure each Cassandra node so that listen_address is set to the private IP address or the node, and broadcast_address is set to the public IP address of the node. This allows Cassandra nodes in one EC2 region to bind to nodes in another region, thus enabling multi-data center support.
Even each node knows about nodes from another DC, they are still unreachable because they have private address. So, how nodes from DC1 are supposed to replicate data to nodes from DC2? It seems assigning broadcast_address the public IP is not enough.
What do I miss?