Understanding vSphere5 Licensing & Changes

Note : VMware has updated their Licensing policy and please find the updated details in this Blog-Post.

With announcement of vSphere5 suite of products  , VMware also introduced changes in licensing policy & vSphere editions that would be available for customers. One must admit that this was coming with the x86 technology evolving at a rapid pace with number of Cores per processor and Size of RAM modules and DIMM slots available increasing in the x86 Servers.

What are the major changes ?

• vSphere 5 licenses would be ” Per Processor ( Physical CPU) with vRAM entitlements”
• Advanced Edition that was available with vSphere 4 has been removed and all customers with vSphere 4 Advanced license with active SnS would be auto upgraded to vSphere5 Enterprise.
• Unlike vSphere4 , There are no more restriction on number of cores that is supported per processor or amount of physical RAM that is supported on a Server

vRAM Entitlements for various vSphere Editions ( Managed by a single instance of vCenter Server or by multiple instances of vCenter Server in Linked Mode) are as follows

• Standard – 24 GB RAM per Processor
• Enterprise – 32 GB RAM per Processor
• Enterprise Plus – 48 GB RAM per Processor
• Essential & Essential Plus –  24 GB RAM per Processor (Only 144 GB RAM total pool allowed per vCenter)
• vSphere Free Edition – 8 GB RAM per Processor

Understanding vRAM entitlements

• vRAM can be defined as the amount of memory that has been allocated to a Virtual Machine.
• vRAM Pool can be defined as Total sum  of vRAM entitlements for all vSphere licenses of a single edition, managed by a single instance of vCenter Server or by multiple instances of vCenter Server in Linked Mode

Let’s take an example , Consider a Virtual Center with 4 hosts of 2 processors & 64 GB RAM each. 2 hosts are licensed for vSphere 5 Standard edition while 2 hosts are licensed for vSphere 5 Enterprise edition. 5  Power On VM’s and 2 Powered Off VM’s are hosted on each of them of configuration 2vCPU /4GB RAM each.

For this example ,

• vRAM of a VM = 4GB
• vRAM Pool eligible for Standard license = 4 CPU’s * 24 GB =48 GB RAM
• vRAM Pool consumed by the VM’s = 4GB * 10 VMs = 40 GB RAM
• vRAM Pool eligible for Enterprise license = 4 CPU’s * 32 GB =64 GB RAM
• vRAM Pool consumed by the VM’s = 4GB * 10 VMs = 40 GB RAM

This licensing changes are applicable only to your vSphere 5 hosts and would not affect your existing vSphere 4 hosts. Would not like to go into detail of if vRAM Entitlement is good or bad since I certainly believe it varies from environment to environment depending on lot of factors like edition of license that is currently being used , size of the hardware in terms of Memory per server , size of the Virtual Machine’s etc..

What I think are the Positive’s on the Licensing changes ?

• Appreciate the fact that instead of restricting vRAM Pool per Server , VMware has allowed to Pool resources across all hosts in a vCenter. This would definitely help customers wherein they could have the flexibility of mixing various hardware configurations in a Single .
• Existing Advanced customer’s would be auto-upgraded to Enterprise license provided they have an active SnS
• Scripts from VMware community to compare existing licenses with that of vSphere 5 editions
• Removes constraints on cores per processor and memory supported on a single server
• Will enable customers to move towards pay for consumption model
• Available and consumed vRAM capacity can be monitored and managed using the licensing-management module of VMware vCenter Server.

What do I think is the Flip Side ?

But I would have definitely liked a higher number on the vRAM supported per processor than that is available now. I do agree that there has been lot of features that has been added as part of vSphere 5 but 48 GB RAM per processor for a vSphere Enterprise plus license is on a lower side even when compared to the existing vSphere4  licenses. We will have to wait and watch on what impact this might have on consolidation ratio and procurement of servers with large Memory. Hardware vendors might not like this but surely competitors of VMware are going to love this ! Remember it’s not only that Server’s RAM capabilities & Capacity are scaling but also the application’s memory requirements. When we talk of Tier 1 applications , Memory requirement is quite high and even if we take an average of 8GB RAM per VM , we might not be able to hold more than 24 VMs on a 4 CPU Server that is licensed for vSphere Enterprise + for 4 Processors.

Complete list of feature comparison between various vSphere 5 editions can be found here.

VMware has updated their Licensing policy and please find the updated details in this Blog-Post.