Hyper-V and the Small Business: 9 Tips for Host Provisioning

The category of questions that I most commonly field are related to host design. Provisioning is a difficult operation for small businesses; they don’t do it often enough to obtain the same level of experience as a large business and they don’t have the finances to absorb either an under-provision or an over-provision. If you don’t build your host large enough, you’ll be buying a new one while the existing still has life in it. If you buy too much, you’ll be wasting money that could have been used elsewhere. Unfortunately, there’s no magic formula for provisioning, but you can employ a number of techniques to guide you to a right-sized build.

1. Do Not Provision Blindly

Do not buy a pre-packaged build, do not have someone on a forum recommend their favorite configuration, and do not simply buy something that looks good. Vendors are only interested in profit margins, forum participants only know their own situations, and no one can adequately architect a Hyper-V host in a void.

2. Have a Budget in Mind

Everyone hates it when the vendor asks, “How much do you want/have to spend?” I completely understand why you don’t want to answer that question at all, and I agree with the sentiment. We all know that if you say that you have $5,000 to spend, your bill will somehow be $5,027 dollars. Unless you have a history with the vendor in question, you don’t know if the vendor is truly sizing against your budget or if they’re finding the highest-margin solution that more or less coincides with what you said you were willing to pay. That said, even if you don’t give the answer, you must know the answer. That answer must truly be an amount that you’re willing to spend; don’t say that you’ll spend $5,000 if what you’re truly able to spend is $3,000. I worked for a vendor of solid repute that earned their reputation, so I can tell you from direct experience that it’s highly unlikely that you’ll ever be sold a system that is meaningfully smaller than what you can afford even if your reseller isn’t trying to oversell. Every system that I ever architected for a small business made some compromises to fit within the budget. The more money they could spend, the fewer compromises were necessary.

3. Storage and Memory are Your Biggest Concerns

Part of the reason that virtualization works at all is that modern CPU capability greatly outmatches modern CPU demand. I am one of the many people that can remember days when conserving CPU cycles was important, but I can clearly see that those days are long gone. Do not try to buy a system that will establish a 1-to-1 ratio of physical CPUs to virtual CPUs. If you’re a small business that will only have a few virtual machines, it would be difficult to purchase any modern server-class hardware that doesn’t have enough CPU power. For you, the generation of the CPU is much more important than the core count or clock speed.

Five years ago, I would (and did) say that memory was your largest worry. That’s no longer true, especially for the small business. DDR3 is substantially cheaper than DDR2, and, with only a few notable exceptions, the average system’s demand on memory has not increased as quickly as the cost has decreased. For the notable exceptions (Exchange and SharePoint), the small business can likely get better pricing by choosing a cloud-based or non-Microsoft solution as opposed to hosting these products on-premises. Even if you choose to host them in-house, a typical server-class system with 32 GB of RAM can hold an 8 GB SharePoint guest, an 8 GB Exchange guest, and still have a good 14 GB of memory left over for other guests (assuming 2 GB for the management operating system). Even a tight budget for server hardware should be able to accommodate 32 GB of RAM in a host.

Storage is where you need to spend some time applying thought. For small businesses that won’t be clustering (rationale on my previous post), these are my recommendations:

• Internal storage provides the best return for your dollar.
• For the same dollar amount, prefer many small and fast disks over a few large and slow disks.
• A single large array containing all of your disks is superior to multiple arrays of subsets.
• Hardware array controllers are worth the money. Tip: if the array controller that you’re considering offers a battery-backed version, it is hardware-based. The battery is worth the extra expense.

Storage sizing is important, but I am intentionally avoiding going any further about it in this article because I want it to be applicable for as many small businesses as possible. There are two takeaways that I want you to glean from this point:

• CPU is a problem that mostly solves itself and memory shouldn’t take long to figure out. Storage is the biggest question for you.
• The storage equation is particular to each situation. There is no one-size-fits-all solution. There isn’t a one-sized-fits-most solution. There isn’t a typical, or a standard, or a usual, or a regular solution that is guaranteed to be appropriate for you. Vendors that tell you otherwise are either very well-versed in a particular vertical market that you’re scoped to and will have the credentials and references to prove it or they’re trying to get the most money out of you for a minimum amount of time invested on their part.

Networking is typically the last thing a small business should be worried about. As with storage sizing, I can’t be specific enough to cover everyone that I’d like this post to be relevant to, but it’s safe to say that 2 to 6 gigabit Ethernet connections per host are sufficient.

4. Do not be Goaded or Bullied into 10 Gigabit Ethernet

I won’t lie, 10 GbE is really nice. It’s impressive to see it in operation. But, the rest of the truth is that it’s unnecessary in most small businesses, and in lots of medium businesses too. You can grow to a few thousand endpoints before it even starts to become necessary as an inter-switch backbone.

A huge part of the reasoning is simple economics:

• A basic business-class 20-port gigabit switch can be had for around $200 USD. You can reasonably expect to acquire gigabit network adapters for $50 or less per port.
• A basic 12-port 10GbE switch costs at least $1,500 USD. Adapters will set you back at least $250 per port.

When you’re connecting five server-class hosts, $1,500 for a switch and $500 apiece for networking doesn’t seem like much. When you’re only buying one host for $5,000 or less, the ratio isn’t nearly as sensible. That price is just for the budget equipment. Since 10GbE adapters can move network data faster than modern CPUs can process it, offloading and VMQ technologies are quite important to get the most out of 10GbE networking. That means that you’re going to want something better than just the bare minimum.

What might even be more relevant than price is the fact that most people don’t use as much network bandwidth as they think they do. The most common tests do not even resemble typical network utilization, which can fool administrators into thinking that they don’t have enough. If you need to verify your usage, I’ve written an article that can help you do just that with MRTG. This leads to a very important point.

5. You Need to Know What You Need

Unless you’re building a host for a brand-new business, you’ve got an existing installation to work with. Set up Performance Monitor or any monitoring tool of your choice and find out what your systems are using. Measure CPU, disk, memory, and networking. Do not even start trying to decide what hardware to buy until you have some solid long-term metrics to look at. I’m surprised at how many messages I get asking me to recommend a hardware build that has little or no information about what the environment is. I’m guessing that the questioners are just as surprised when I respond, “I don’t know.” It doesn’t take a great deal of work to find out what’s going on. Do that work first.

6. Build for the Length of the Warranty

Collecting data on your existing systems only tells you what you need to know to get through the first day. You’re probably going to need more over time. How much more depends on your environment. Some businesses have reached equilibrium and don’t grow much. Others are just kicking things off and will triple in size in a few months. Since those truly new environments are rare, I’m going to aim this next bit at that gigantic majority that is building for the established institutions. Decide how much warranty you’re willing to buy for the new host and use that as your measuring stick for the rest of it. How you proceed depends upon growth projections:

• If the system needs won’t grow much (for example, 5-10% annually), then build the system with a long warranty period in mind. If the business has been experiencing a 5% average annual growth rate and is currently using 300 GB of data, a viable option is to purchase a system with 500 GB of usage storage with a 5-year warranty.
• If the system needs will grow rapidly, you have two solid options:
  • Buy an inexpensive system with a short warranty (1-3 years). Ensure that it’s understood that this system is not expected to live long. If decision-makers appear to be agreeing without understanding, you’re better off getting a bigger system.
  • Buy a system that’s a little larger with a longer warranty (5 years). Plan a definite growth point at which you will scale out to a second host. Scaling out can become more than twice as expensive as the original, especially when clustering is a consideration, so do not take this decision lightly.

Most hardware vendors will allow warranty extensions which give you some incentive to oversize. If you make a projection for a five-year system and it isn’t at capacity at the end of those five years, extending the warranty helps to maximize the initial investment.

In case it’s not obvious, future projections are much easier to perform when you have a solid idea of the environment’s history. There’s more than one reason that I make such a big deal out of performance monitoring.

7. Think Outside the One Box

Small businesses typically only need one physical host. There isn’t any line at which you cross over into “medium” business and magically need a second host. There isn’t any concrete relationship between business size and the need for infrastructure capacity. Just as I preach against the dangers of jumping into a cluster needlessly, I am just as fervent about not having less than what is adequate. Scaling out can undoubtedly be expensive, but when it’s time, it’s time.

Clustering isn’t necessarily the next step up from a single host. Stagger your host purchases across years so that you have an older system that handles lighter loads and a newer system that takes on the heavier tasks. What’s especially nice about having two Hyper-V hosts is that you can have two domain controllers on separate equipment. Even though I firmly stand behind my belief that most small businesses operate perfectly well with a single domain controller, I am just as certain that anyone who can run two or more domain controllers on separate hosts without hardship will benefit from the practice.

8. Maybe Warranties are Overrated

I’ve been in the industry long enough to see many hardware failures, some of legendary quality. That doesn’t change the fact that physical failures are very nearly a statistical anomaly. I work in systems administration; my clients and workers from other departments never call me just to be social. Anyone in my line of work deals with exponentially more failures than anyone outside my line of work. So, while I am probably always going to counsel you to spend extra so that you can get new or something that is new enough that you can still acquire a manufacturer’s warranty on it, I can also acknowledge that there are alternatives when the budget simply won’t allow for it.

In my own home, most of the equipment that we use is not new. As a technophile, I have more computers than people, and that’s before you start counting the devices that don’t have keyboards or the units that are only used for my blogging. I rarely buy anything new. I am unquestionably a fan of refurbished and cast-off systems. It’s all very simple to understand: I want to own more than I can technically afford to own, and this practice satisfies both my desire for tech and my need for frugality. Is that any way to run a business? Well…

Cons of Refurbished and Used Hardware

One the one hand, no, this is not a good idea. If any of this fails, I have to either repair it, live without it, or replace it. If you don’t have the skills for the first, the capacity for the second, or the finances for the third, that leaves your business in the lurch. If you’d have to make that choice, then no, don’t do this. Another concern is that if you’re doing this to be cheap, a lot of cheap equipment doesn’t meet the criteria to be listed on http://www.windowsservercatalog.com and might be more trouble than the savings is worth. And of course, even if it’s good enough for today’s version, it might not work with tomorrow’s version.

For another thing, I’ve seen a lot of really cheap business owners use equipment that they had to repair all the time and that was so inefficient that it impacted worker productivity. That sort of thing is a net loss. Avoid these conditions, even if it means spending more money. Remember what I said earlier about compromises? Sometimes the only viable compromise is to spend more money on better hardware.

If you go the route of having hardware that doesn’t carry a warranty, you need to be prepared to replace it at all times. Warranty repairs are commonly no longer than next-business-day in this era. Buying replacement hardware could have days or even weeks of lead time. Having replacement hardware on hand can cost more than just buying new with warranty.

Pros of Refurbished and Used Hardware

On the other hand, I spent less to acquire many of these things than their original owners did on their warranties, and, with the law of averages, most of my refurbished equipment has never failed. I quite literally have more for less. Something else to remember is that a lot of refurbished hardware is very new. Sometimes they’re just returns that can no longer be sold as “new”. You can often get original manufacturer warranties on them. The only downside to purchasing that sort of hardware is that you don’t get to pick exactly what you want. For the kind of savings that can be had, so what?

In case you’re curious, all of the places that I’ve worked pushed a very hard line of only selling new equipment. “Used” and “refurbished” carry a very strong negative connotation that no one I worked for wanted to be attached to. However, I didn’t work for anyone that would turn away a client that was using used or refurbished equipment that they acquired independently. I’ve encountered plenty of it in the field. It didn’t fail any more often than new equipment did. I’ll say that I do feel more comfortable about “refurbished” than “used”. I also know what it’s like to be looking at a tight budget and needing to make tough decisions.

I will say that I would prefer to avoid used hardware for a Hyper-V host. I understand that it can be enticing for the very small business budget so I will stop short of declaring this a rule. It’s reasonable to expect used hardware to be unreliable and short-lived. Used hardware will consume more of your time. Operating from the assumption that your time has great value, I encourage you to consider used hardware as a last resort.

9. Architect for Backup

I expect point #8 to stir a bit of controversy. I fully expect many people to disagree with any notion of non-new equipment, especially those that depend on margins from sales of new hardware. I don’t mind the fight; until someone comes up with 100% failure-free new hardware, there will never be a truly airtight case for only buying new.

If you want to give yourself a guaranteed peace of mind, backup is where you need to focus. I may not know the statistics around failures of new versus used or refurbished equipment, but I know that all hardware has a chance of breaking. What doesn’t break due to defect or negligence can be destroyed by malice or happenstance, so you can never rely too much upon the quality of a purchase.

What this means is that when you’re deciding how many hard disks to buy and the size of the network switch to plug the host in to, you also need to be thinking about where you’re going to copy the data every night. External hard disks are great, as long as they’re big enough. Offsite service providers are fine, as long as you know that your Internet bandwidth can handle it. If you don’t know this in advance, you run the risk of needing to sacrifice something in your backup rotations. I have yet to see any sacrifice in this aspect that was worth it.