Why should you read this blog post?
Comparing storage solutions pricing was always complicated and now with new emerging architectures like Hyper-converged (HCI), it can become an even more daunting assignment. Figuring out how to get to a fair comparison, or as close to an apples-to-apples one, is really not trivial. I’ve spent many hours trying to figure things out, and could find very little guidance online. I hope this blog post will save you a few hours if you’re considering VMware’s HCI solution - Virtual SAN, and the steps outlined here might also come handy when comparing any other two storage solutions. So let’s get to it.
Step 1: What are your requirements?
A lot of people start a pricing comparison by jumping to the end and ask “How much 50TB of VSAN will cost me?” – That’s a legitimate question for a typical storage product, but Virtual SAN is not a typical storage product. Virtual SAN is a software product built for Hyper-converged Infrastructure – that means you deploy Virtual SAN on top of your x86 servers, typically adding SSDs and HDDs, unless you already had them there. Virtual SAN will pool the storage in your x86 servers to deliver the same shared storage functionality you are used to getting from your current/typical storage array.
Now you ask – “OK – so why can’t I get a price per TB/GB like from my storage vendor?” – The answer is that Virtual SAN is not sold as a dedicated hardware or even as an appliance – it gives you, the customer, full flexibility of choice to deploy your workloads with exactly as much storage as you want – no need for expensive upfront investments.
So now you must think – “OK and how do I know how much I need?” – That’s where you have a couple of options:
- Virtual SAN Assessment – a new service which was released recently allowing you to deploy a collector in your environment that will track your storage usage and consumption and will provide you with the data points to input into our Virtual SAN Sizing and TCO Calculator. If you're interested in a Virtual SAN Assessment, you may request one here.
- Manual – bring your own estimates of how many VMs, VM sizes, consolidation ratios, etc. and manually insert the data points into our Virtual SAN Sizing and TCO Calculator.
Step 2: Size Your Virtual SAN
Once you have the data points on your required environment you’ll need to size Virtual SAN. There’s a handy blog post I wrote that can help you understand what each input point means, and what you need to pay attention to. Since I wrote the blog the tool went through some updates, but the core principals stayed the same – I will publish an update to the blog soon. In the meantime, feel free to leave questions in the comments sections below.
When you finish your sizing you’ll get the results in the following format:
As you see this includes how many TB you’ll need, how much you’ll be able to use, and what is the expected performance of the Virtual SAN Cluster, etc. Not happy with what you see? Just go back, adjust your assumptions around the environment size, adjust the hardware configuration and see how things change. In the next steps you can use the TCO part of the calculator to help you with the comparison.
Step 3: What’s Your Time Horizon?
Now that you know what is your desired Virtual SAN environment will look like. You need to think about your time horizon. Hardware upgrade cycles for storage and servers can vary and will significantly impact your budget and planning – so that’s the first question you’ll need to answer. Neglecting to take into account refresh cycle costs, can impact your ability to deploy additional storage when you need to, or have enough compute and storage resources available when a planned project gets into the implementation stage.
Note, that you won’t need to buy additional Virtual SAN licenses unless your environment grows. Much like vSphere you can move your licenses to the new bought hardware.
Step 4: What license should you purchase?
Virtual SAN comes in several flavors. There’s the Standard and Advanced editions, that are priced per-CPU, and apply to all use cases, but there are also two use-case based licenses – one for Virtual Desktops (VDI), and one for Remote Office Branch Office (ROBO). If you are looking to deploy VSAN for one of these use cases, these licenses should be able to save you money on licensing, so explore them first.
Note that the calculator supports both Per-CPU and desktop licenses, but still doesn’t have the ROBO ones in it – this will come in a future update. If you picked Desktop Virtualization in the first step of the sizing process the VDI license options will automatically be populated for you in the calculator.
In regards to deciding between advanced and standard licenses it depends on the type of workloads you are going to run on VSAN. If you require consistent high performance, with sub-millisecond latencies and/or you plan to be able to recover from a site failure, you’ll most likely want to take advantage of the All Flash and Stretched cluster features in Virtual SAN Advanced. Otherwise, Virtual SAN Standard should provide you all the core functionality you’ll need for standard workloads.
Step 5: Include Support?
Another common mistake we see is that Subscription and Support (SnS) is added to the cost of purchasing Virtual SAN, while no support costs are taken into account no the other storage solution. This can make Virtual SAN look expensive, while the reality is that it's significantly more cost effective. Support on alternative storage solutions varies and is typically a percentage of the list price, regardless of any discounts your organization was able to negotiate.
In the TCO calculator we made it convenient to include SnS and support on an alternative solution as percent of the list price cost.
In the second part of this blog, I’ll discuss how to look at alternatives, what attributes to pay attention to if you’d like to enter your own customized comparison, how to take into account operational benefits that Virtual SAN provides, and should you pay attention to when reviewing the TCO results.