You need the following tools and software for the upgrade process. Except for Rufus, you can download the software from the Avaya Support site (https://support.avaya.com).
IP Office R11.0.4.8 server PC ISO file
The iso file name starts with "abe" followed by the version.
R11.1 upgrade VMDK file
You add this file to the virtual machine as an additional drive. When the virtual machine reboots from this drive, it upgrades the virtual machine to R11.1.3.