For Nutanix Disaster Recovery, paired Prism Central instances manage the disaster recovery configuration, including protection policies and recovery plans. This management communication between the two Prism Central availability zones (AZs) occurs over TCP port 9440. This port must be open bidirectionally to allow for initial pairing, subsequent configuration synchronization, and orchestration of failover and failback operations.

A. 2009: This port is used for communication between Controller VMs (CVMs) within a cluster for data replication, not for Prism Central to Prism Central management.

B. 2020: This port is used for communication between CVMs for configuration tasks, not for inter-Prism Central communication.

C. 2074: This port is used specifically for the Nutanix DRaaS (Xi Leap) VPN gateway connection and is not required for DR between two on-premises Prism Central instances.

1. Nutanix Port and Protocol Reference v2.6, "Prism Central Based Disaster Recovery (DR)" section, Page 11. The table specifies that for communication between a source Prism Central and a remote Prism Central, TCP port 9440 is required.

2. Nutanix Disaster Recovery Guide v6.8, "Prerequisites for Disaster Recovery Between On-Prem AZs" section. It states, "Ensure that the Prism Central instances at both the primary and recovery AZs can communicate with each other over the port 9440."