Disclaimer: I’ve been awarded vExpert by VMware, and I love their products. At the same time I’m a consultant and I work for my customer, and my goal is to find out for them always the best solution. This post is not a “public bashing”, but a way to think about all the consequences new licensing can possibly bring. The opinions you will find here are obviously mine
Finally version 5 of vSphere, two years from v4 announcement, has arrived.
You will find on the official VMware website and in the blogosphere several articles, blog posts and info about all the new introduced features. For sure I will too talk about them.
Anyway I’ve seen on twitter the hottest topic was licensing, and it could not have been otherwise.
If many of the features are a logical and expected evolution (mark well, they are not average, but nost of them were already known or expected) licensing has changed radically.
VMware has indirectly admitted that socket licensing, also base on maximum number of cores per socket, simply was not reflecting anymore the evolution of underlying hardware. Was not feasible for example using two standard licenses to use a 8 core cpu.
So, along with vSphere 5, has arrived a new licensing schema, and you can read it by yourself in this pdf. Its usage can be summarized in these points:
– licensing is still based on sockets
– cores per socket are not limited anymore
– every CPU license brings with it a “dowry” to the datacenter a entitled ram, that is an amount of licensed RAM
– Advanced version is no more available (must be upgraded to Enterprise)
– differences between versions (Essentials, Essentials Plus, Standard, Enterprise, Enterprise Plus) are both available features, and also entitled RAM per CPU. This schema taken from the licensing paper summarizes the values:
RAM can be aggregated in a vRAM Pool, that will be the total amount of licensed RAM.
There is anyway a concept that must be explained to have a full vision: licensing talks about Assigned RAM and not Consumed RAM. That is, a virtual machine created with 4 Gb ram that’s using 1 Gb ram of the hosting ESXi, will be counted as 4.
If at this point you are puzzled and you have some doubt, you are not alone: during yesterday’s (in Italy) announcement twitter has become a madhouse. But instead of going for a love/hate situation, we all have to try and simulate real cases, because I think there will be for sure situations where things will be better than the past, and other worse.
Keep in mind these thinkings, coming in open order while thinking them:
– ram limit per pool is soft. Vcenter will send out warnings near the reaching of the limit declared by the total amount of licensed RAM. Only Essentials bundle will have a hard limit at 144 Gb.
– generally, ram values per CPU seems low to me. reality is servers are becoming more and more able of managing huge amounts of ram, and a simple 2 socker 4 core server can handle way more than 96 gb of ram. With Enterprise Plus, that server can handle 96 Gb. During the announement there has been talks about huge VMs, but to manage them there will be the need for a suitable vRAM pool. There will be situations where licensed CPU will need to be more than the physical CPU, just to have a sufficient vRAM pool. For example the biggest max VM with 1 Tb ram will require 22 new Enterprise Plus licenses, even if it will obviously run on a single node at a time.
Let’s do a fast comparison: a virtual machine with 255 Gb ram hosted on a single server with dual socket. Using Enterprise Plus licenses, with VS4 you need only 2 licenses, now you will need 6.
I really would like to see scenarios where we will have savings compared to VS4, in the short time I got between announcement and this post I had no time to do deep simulations. At first sight every configuration with more ram than those allowed by entitled RAM of a given server seems disadvantegous, for example going over 192 Gb on a quad socket licensed with Enterprise Plus. But still huge VMs (but smaller than those managed by VS4, here the limit for not overbuying ram seems 192 gb instead of 255…) needs to be licensed by their assigned ram, and you need underlying servers with that amount of ram to run them…
– to measure assigned ram is a shot to technologies like page sharing, compression, e all capacity planning tools, tuning etc… Why do I need to care about page sharing if at the end I will pay for assigned RAM?
I’m really waiting for documents and detailed articles about this, because I love the product, and I’m sad this new licensing has diverted attentions from the new advanced features of vSphere 5.
And that’s the most unpleasant error…
PS: I want to say it again. From a technology point of view, vSphere 5 ROCKS!