After you have successfully replaced the PTM Appliance, you can remove Disk 3 (/vastorage_old). You must stop the VM to remove the disk.
In a web browser, go to the Appliance Management Console URL for the replacement PTM Appliance, then and log in as the vaadmin user.
https://ip_address_or_DNS_name:9443
In the Appliance Management Console, click Shutdown.
Wait for the Appliance VM to shut down gracefully.
In the vSphere Client, remove Disk 3 (/vastorage_old).
Right-click the replacement VM in the vSphere Client, and click Edit Settings.
Select Disk 3 (/vastorage_old), then click Remove.
Click OK.
(Optional) In the vSphere Client, delete the .vmdk file for Disk 3 (/vastorage_old) from the datastore.
In the vSphere Client, power on the replacement VM.
The PTM services are started automatically.