If you are completing a security audit or setting up a firewall, you probably need details about the ports used by your Nutanix cluster.
Thankfully, we have a reference provided which explains the ports needed by various services on an AOS cluster.
You can find out about ports used by different AOS services in the KB article Port numbers used for inter CVM communication .
The Security Guide found in our software documentation library is the best reference for firewall rules, which are detailed in this section. The Security Guide details which ports should be open and to what URL(s) specifically for Remote Support (reverse SSH tunnel), Pulse, Alerts (call-home for automatic case creation), SMTP sending, Data Replication to remote clusters, 1-click upgrades, and LCM.