I was building a lab on Oracle Ravello Cloud and I wanted to install VMware vCenter Virtual Appliance 6.5 on a deployed ESXi host. I started the deployment as usual and the deployment failed in the middle of the VCSA configuration. It was not able to power on and below error message deployed in the ESXi host client. “Failed to power on virtual machine <VM_NAME>. You are running VMware ESXi through an incompatible hypervisor. You cannot power on virtual machine until this hypervisor disabled“. See below error message.
So I tried to manually Power on the Virtual Machine and was not able to do that and ended up with the same error message again and again.
I found this KB article and I tested this with a test VM. I used the Webclient to add “vmx.allowNested = TRUE” parameter to the test VM under Edit Settings and advanced parameters.
Fortunately, test VM started and I tried to do the same thing for my vCenter VM unfortunately, it didn’t work and failed with this error message “A specified parameter was not correct: unitNumber“.
Anyway at that time my deployment was failed and I deleted the vCenter VM and started the process again. Once it started the deployment, it created the VM inside the ESXi host, so I opened a SSH session to the ESXi host and edited the .vmx file and added the “vmx.allowNested = TRUE” parameter at the end of the .vmx file. At that time deployment process didn’t start the VM and just created the VM in the host’s inventory.
I was monitoring the deployment status and it was successfully deployed my vCenter Server Appliance at this time.
References : VMware KB Article (2108724)