Some questions about setting public/private IP-Addresses in Cassandra Cluster

[Ajay Garg <aj...@gmail.com>]

Hi All.

We have a scenario, where the Application-Server (APP), Node-1 (CAS11), and
Node-2 (CAS12) are hosted in DC1.
Node-3 (CAS21) and Node-4 (CAS22) are in DC2.

The intention is that we provide 4-way redundancy to APP, by specifying
CAS11, CAS12, CAS21 and CAS22 as the addresses via Java-Cassandra-connector.
That means, as long as at least one of the 4 nodes are up, the APP should
work.

We are using Network-Topology, with Murmur3Paritioning.
Each Cassandra-Node has two IPs :: one public, and one
private-within-the-same-data-center.


Following are our IP-Addresses configuration ::

a)
Everywhere in "cassandra-topology.properties", we have specified
Public-IP-Addresses of all 4 nodes.

b)
In each of "listen_address" in /etc/cassandra/cassandra.yaml, we have
specified the corresponding Public-IP-Address of the node.

c)
For CAS11 and CAS12, we have specified the corresponding private-IP-Address
for "rpc_address" in /etc/cassandra/cassandra.yaml (since APP is hosted in
the same data-center).
For CAS21 and CAS22, we have specified the corresponding public-IP-Address
for "rpc_address" in /etc/cassandra/cassandra.yaml (since APP can only
communicate over public IP-Addresses with these nodes).


Are any further optimizations possible, in the sense that specifying
private-IP-Addresses would work?
I ask this, because we need to minimize network-latency, so possibility of
private-IP-addresses will help in this regard.


Thanks and Regards,
Ajay