https://www.cisco.com/c/en/us/td/docs/net_mgmt/cisco_secure_access_control_system/5-5/user/guide/acsuserguide/admin_operations.html lists ports used by ACS, however it doesn't differentiate between ones used to communicate with the ACS and which ones are used for Intra-Cluster communication.
Is this summary accurate?
ACS External Communication: TCP 22, 49, 443, 1812, 1813, 1645, 1646, 3799; UDP 161, 162, 9993, 20514
Intra-Cluster Communication: TCP 443, 2020, 2030, 2638, 61616