New finding while trying to import the existing virtual machine from ESX 3.5 to vSphere 4 ESX host. I got an image from previous ESX 3.5 which is running hardware version 4. I was trying to import it to the new ESX 4.0 through the import wizard, and been failed for couple of times. During the wizard, it allow you to change the virtual machine name, thin provision, disable unnecessary services and upgrade to virtual hardware version 7. I had selected the necessary configuration but non of it were success. It had always failed at the stage of 12 % during the import process. I even had browse the datastore to monitor the progress, for unknown reason, the task will be failed for no reason, which not even a packet was drop during the process.

I decide to do a final round of import which keep every single configuration as default. All the configuration of the existing VM had not been changed and it works. After the success import, I had to manually update the vmtools and virtual hardware version. I had also cloned the virtual machine to the new VM name that I wanted to, with thin provision enable. It had been taken 6 hours for the entire import process, which is consider long as the virtual machine image was 400GB. I will suggest to leave the default setting for future import process as it shown as more consistent process. The rest of the configuration always can be done right after the success import.