Article by:Jeff Woolsey

Question of the Day

Q: When I go to the network control panel within a virtual machine, the connection speed is displayed as 10.0 Gb/s. I don’t have a 10 Gb/s network adapter in my system. What’s the explanation?

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A: We have to label the Hyper-V virtual NIC with some moniker and arbitrarily chose 10GB/s. It’s all in software, so the actual limit is whatever your hardware and processing resources can throw at it. We had the same exact problem with Virtual Server many years ago. In Virtual Server, our NIC reported itself to be a 100 Mb NIC. As a result, we’d receive regular email asking why we didn’t support 1 Gb/E and when we were going to upgrade our virtual NIC. In reality, this NIC could far exceed 100 Mb, but that didn’t matter because the little balloon said 100 Mb.

Now, we’re at Hyper-V and we have to choose a value again:

· If we choose 1 Gb/E, we’re doing ourselves a disservice because Hyper-V easily exceeds 1Gb/E performance.

· If we choose 10Gb/E, we may or may not hit this value depending on a variety of factors

So, you’re probably asking, well, what’s the real number? The answer is <drum roll please>…

It depends. It depends on numerous variables such as:

· CPU, Speed of CPU

· Speed of memory

· How many VMs are running 1, 5, 20, 50?

· Etc.

Bottom line: We had to choose a value, no matter what value we choose no one will be happy, but 10Gb seemed the most appropriate.