Hardware load balancers and virtual load balancers are two of the most common load balancing platforms. But what's the difference? Don't get me wrong. This is not a blog telling you what appliance you should buy. It's simply a blog explaining the core differences, as well as the advantages and disadvantages of each. Because we get asked this - a lot.
So, let's start with the classic hardware load balancer...
A hardware load balancer is like a CD player. You can pick it up, play music on it, and it’s perfectly reliable. When it's old, you can replace it. Virtual is like an MP3 file. The same quality, but you need to find something to play it on!
The main reason to choose a hardware unit is that it guarantees you speed. At the end of the day, you are protected from the dreaded ‘noisy neighbour’ syndrome.
With virtual, whilst you can allocate resources, if you max out resources to the virtual machine, something will always have to give. So it's not guaranteed.
The downside of hardware is that it's another machine to maintain, and if you have a large server estate things can get complicated. How do you track the hardware warranty for multiple servers? When do you replace the hardware - 3 years, 5 years, 7 years…?
What will you do with all the extra space if you opt for virtual?
The main advantage of virtualization is that you have the flexibility to move the software running on it to another virtual server. Obviously you still have hardware sitting under it, but replacing and migrating the software is easier because of the virtualization magic.
Another difference is the price. 9 times out of 10, the virtual price is lower than the hardware equivalent. This is because you don't have to pay for the physical hardware kit.
But is there a performance hit for going virtual? Yes, absolutely. Each virtual appliance (VA) you use will cut some of the power of the virtual machine (this is usually between 10% or 15% but of course will vary depending on which type of VA you use). So the virtual load balancer will always be slightly slower than the hardware equivalent. That's not to say virtual load balancers are bad. In fact, for many deployments, they are actually quite good and have a range of advantages.
When you buy hardware, it comes with a spec/resource that you can't use somewhere else. But virtual means you only need to allocate the resources you need. Right out of the box our VA allocates a set number of resources, but these can then be increased (or decreased) as you see fit. So you can spread the resources of your virtual machine across many applications.
Overall, hardware, therefore, has the advantage of being designed specifically to handle what it does. But if you host your virtual on a powerful enough virtual machine, then you could (in fact) have a very good load balancer - knocking at the door of the hardware counterpart.
Why is F5's hardware so great?
One word. FEATURES! F5 is all singing and dancing. The Rolls-Royce of load balancing. If you want a specific feature, they probably have it.
Unfortunately for most people and companies, they have the price tag to match. Not a problem if you're a huge company with a massive budget, but just because you can afford it, does that mean you should buy it? No, of course not. Gone are the days when you'd get fired if you didn't buy an F5.
Does this mean then that F5 hardware has the best features? Yes. Should you replace your current load balancer with F5 just because it's the most feature-rich? No, of course not!
Have a think about your individual load balancing requirements and decide what you need, instead of what you think you want. The likelihood is that you don't need all the bells and whistles that an F5 has to offer. So why pay more?
"You would say that — you work at Loadbalancer.org for goodness sake," you might say. "What's so great about a Loadbalancer.org appliance?"
Bottom line. If you want to only pay for what you actually need, then we're for you. But if you can afford a catch-all solution, then F5 may be a better bet. And we fully support you in that decision! At the end of the day, you need to find a load balancing vendor that can serve your individual needs. And there is most definitely a lot to choose from! But if you're at the point where you're considering your options, and you're interested in testing our solution to determine whether or not we can meet your needs, then download our free trial and decide for yourself.