You can create a custom application and configure it so that vCenter Server can use it to generate computer names or IP addresses for guest operating system customization.

The application can be an arbitrary executable binary or script file appropriate for the corresponding operating system in which vCenter Server is running. After you configure the application, each time you initiate a guest operating system customization for a virtual machine, vCenter Server executes the application and an XML string is generated in place and passed to its standard input.

Use the attached reference file to create an application for vCenter Server. The application must comply with the reference file.

For instructions about configuring parameters for the application and information about guest OS customization requirements, search for Configure a Script to Generate Computer Names and IP Addresses During Guest Operating System Customization in the vSphere Client in the VMware vSphere 6 documentation .

From vSphere 8.0, you should also follow below 3 additional requirements:
1. Ensure the application doesn't execute privileged actions.
2. Upload the application onto the vCenter Server system's directory /var/run/vpxd with world readable permission.
3. Regarding to the text file containing lines of ip address, hostname and vm name, upload it onto the vCenter Server system's directory /var/run/vpxd with access permission mode 0644 and change file owner to vpxd (command: chown vpxd ip.txt).