Which file is used to open up a non-standard firewall port to the vault?

The file used to open a non-standard firewall port to the vault is dbparm.ini. This configuration file plays a critical role in defining database connection parameters for the CyberArk vault, including settings related to network communications. Within dbparm.ini, administrators can specify the port number that the CyberArk components should use to communicate with the vault, which is essential when needing to open additional ports beyond the defaults.

While other options are associated with various CyberArk components and settings, they do not specifically manage firewall port configurations for accessing the vault. For instance, vault.ini primarily contains settings related to the overall vault functioning and security configurations, while padr.ini deals with settings pertinent to the Password Rotation Distributed (PADR) service. cpm.ini relates to the Central Policy Manager's parameters but does not influence the database connection ports directly. Thus, dbparm.ini is the correct choice for managing non-standard firewall ports for vault communication.