Explanation: This is the correct answer because the Vault.ini file on the CP machine contains the configuration settings for the CP to connect to the Vault server. The Address parameter specifies the IP address or hostname of the Vault server that the CP will use to communicate with the Vault. In the event of a failover of the Vault server from the primary to the DR, the CP needs to update the Address parameter with the IP address of the DR Vault server in order to continue being able to refresh its cache. The cache is a local storage of credentials that the CP retrieves from the Vault and provides to the applications. The cache is refreshed periodically based on the RefreshInterval parameter in the Vault.ini file. This answer is based on the CyberArk Secrets Manager documentation1 and the CyberArk Secrets Manager training course2.
The other options are not correct because they do not ensure that the CP will continue being able to refresh its cache in the event of a failover of the Vault server from the primary to the DR. Adding the DR Vault IP address to the Address parameter in the main_appprovider.conf.. file in the AppProviderConf safe is not a valid option, as this file does not contain the Address parameter. The main_appprovider.conf file contains the configuration settings for the basic provider, such as the AppProviderVaultParmsFile, the AppProviderPort, and the AppProviderCacheMode. The Address parameter is only found in the Vault.ini file on the CP machine.
In the Password Vault Web Access (PVWA) UI, adding the IP address of the DR Vault in the Disaster Recovery section under Applications > Options is not a valid option, as this section does not exist in the PVWA UI. The PVWA UI does not have a Disaster Recovery section under Applications > Options. The PVWA UI has a Disaster Recovery section under Administration > Options, but this section is used to configure the DR Vault settings, such as the DR Vault IP address, the DR Vault user, and the DR Vault password. These settings are not related to the CP configuration or cache refresh.
In the Conjur UI, adding the IP address of the DR Vault in the Disaster Recovery section under Cluster Config > Credential Provider > Options is not a valid option, as this section does not exist in the Conjur UI. The Conjur UI does not have a Cluster Config, Credential Provider, or Options section. The Conjur UI has a Cluster Config section under Settings, but this section is used to configure the Conjur cluster settings, such as the master IP address, the follower IP address, and the seed fetcher IP address. These settings are not related to the CP configuration or cache refresh.