In vSphere 5 the licence you use (Standard, Enterprise or Enterprise plus) is partly determined by how much vRAM the virtual machines have been allocated.
vRAM is new in Version 5, Unlike in vSphere 4 where the core and physical RAM entitlements are tied to a single server and cannot be shared among multiple hosts, the vRAM entitlements of vSphere 5 licenses are pooled, aggregated, across all vSphere servers managed by vCenter Server.
So what is a vRAM?
When a virtual machine is created, it is configured with a certain amount of memory available to the virtual machine, this is called vRAM.
What are the new Licences?
The licences are split up into 3 different versions...
- Standard 1 Processor licence allow for a maximum of 32GB/entitlement
- Enterprise 1 Processor licence allow a maximum of 64GB /entitlement
- Enterprise plus 1 Processor licence allow a maximum of 96GB/entitlement
So how do I licence Servers and vRAM?
The easiest way to explain it is to provide an example.
If you were to use two DL380 G7 servers each with two 6 core processors (4 processors in total), 128GB of physical RAM and you wanted to use vSphere Enterprise edition, each physical CPU would require a license. To correctly licence vShpere you would need to purchase a minimum of four vSphere 5 Enterprise licenses (one for each processor). Now as each Enterprise license provides a vRAM entitlement of 64GB this creates a vRAM pool of 256GB.
Next, you would need to create the virtual machines.
In this example lets say you want to create 50 virtual machines each having 4GB of vRAM in each, and planned to deploy them across the two DL380 G7 servers, this would only take up 200GB of your 256GB entitlement. As both of the DL380 servers are connected to the same vCenter Server and are running the same VMware vSphere edition This vRAM pool also allows DRS and VMware vMotion to move the virtual machines between any of the CPUs without needing any additional licenses.
Even if all 50 virtual machines were running on a single CPU, no additional vRAM capacity would be required, because the pooled vRAM entitlement would not be exceeded.
If you increased the memory in the DL380 servers to beyond the vRAM entitlement, you would need to purchase additional processor licences (of the same type) for the additional physical memory you installed in the servers to be used.
For instance If you increased the memory in the servers from 128GB to 192GB each (384GB in total) but only had the 4 Enterprise licences as shown above, you would only ever see an entitlement of 256GB of that 384GB. You would therefore need to purchase another 2 enterprise licences to allow the additional memory in the servers to be used.
So what do the different versions give me?
Below is a table showing what features are with each edition of vSphere 5
I Hope that has helped with any questions around licencing vSphere 5.
If you have any questions please post them below and i will be happy to help or please contact us.
Regards
Technical ISS Solutions Team
