How should an administrator enable secure access to Volumes using a password?

https://portal.nutanix.com/page/documents/details/?targetId=Web-Console-Guide-Prism-v50:wc-bl ock-services-enabling-t.html

Provision storage on the Nutanix cluster by creating a volume group. Create a client whitelist to enable access to the volume group by using the IP addresses or client initiator IQNs in a whitelist (as part of the volume group configuration). Create a secret for the volume group if you are using CHAP authentication.