In the help (As part of pega 7.1.9 upgrade guide ) for elastic search, we have found out that we need to "open a TCP port in the range 9300-9399 on each node. Should not be externally accessible and it is only for node-to-node communication".
For hazelcast apart from the difference in ports 5701-5800, these ports should not be externally accessible as well?
Pega 7 Platform uses Hazelcast distributed clustering technology to share data and send events between server nodes.
The default port range for Hazelcast communication between nodes in a cluster is 5701 through 5800. I don't see any reason for keeping these ports open for external access. This port range is purely for cluster communications across the nodes and pretty much similar like Elastic search.