With PowerCLI, you can start and stop virtual appliances, and modify their properties.

Connect to a vSphere server.

1

Get the virtual appliance named VApp and stop it.

Get-VApp VApp | Stop-VApp -Confirm:$false
2

Change the name and memory reservation for the VApp virtual appliance.

Get-VApp VApp | Set-VApp -Name OldVApp -MemReservationMB 2000