Hi Schepp.
Thank you for your swift response.
We have VCenter Server installed. ESXi version is 5.1 standard.
VMs are located on ESXi host local disks, but they can access disks located on a SAN drive array shared by both ESXi hosts.
VMs have at least 4 cores (cpu ?).
Regarding the licences point, what do you mean exactly ?
Regards,