How to reinstall a Single ESXi Host Running Your vCenter

Some quick notes on how I reinstalled my homeserver from 6.7 to 7 without losing any VM configuration

The Challenge

I was still running ESXi 6.7 from a usb-stick and I knew that going forward VMWare is no longer going to support this type of setup. So how am I going to reinstall the host from scratch that also hosts my vCenter without losing all my VM configurations ? Recipe:

• Shutdown all VMs except vCenter
• Make note if you have any VMs with manual mac addresses. If so collect that information
• Run the following one-liner from Powercli to save the location info of the VM’s to a csv file

• Get-VM | Select Name, @{N="VMX";E={$_.Extensiondata.Summary.Config.VmPathName}} | Export-CSV -Path "c:\temp\vm-info.csv" -NoTypeInformation
  

• IMPORTANT: in vCenter disconnect the host (right-click, disconnect)
• Remove any PCIE passthrough & zwave USB devices from the VMs
• Shutdown vCenter
• Shutdown the host
• Remove the ESXi 6.7 USB thumbdrive
• Install ESXi 7 to a local SSD using the same hostname & IP
• After installation run this script to re-register all VMs again

• connect-viserver "esxi7-host.local"
  $csv = Import-Csv -Path 'C:\temp\vm-info.csv'
  foreach ($row in $csv){
    write-host "registering" $row.name -ForegroundColor Green
    $vm = $row.name
    $vmxpath = $row.VMX
    Write-Host "VM name is:" $vm
    Write-Host "vmx path name is:" $vmxpath"
    New-VM -Name $vm -VMFilePath "$vmxpath"
    Write-Host ""
  }
  

• select devices for passthrough (a HBA in my case) and reboot after selecting
• attach the PCIe device back to the VM
• attach attached usb devices back to its VM
• Start vCenter, login, select the host and click: “Connect”. Accept the new certificate Done!