Organizations that have invested in a SAN typically have physical servers that connect directly to SAN storage through a Fibre Channel connection. Previously, such servers were considered to be poor candidates for virtualization because hypervisors lacked an efficient way to link the virtual machine (VM) to SAN storage. The new virtual Fibre Channel (FC) feature in Microsoft's Hyper-V 3.0 solves this problem by making it possible to link a virtual machine directly to SAN storage.
To use virtual Fibre Channel, a VM must be running on Hyper-V 3.0 and its guest operating system must run Windows Server 2008 or higher. Likewise, the host server must be equipped with a host bus adapter (HBA) that supports N_Port ID Virtualization (NPIV), and the NPIV feature must be enabled.
If an organization plans to use live migration for a VM that uses virtual Fibre Channel, any node that could potentially host the VM must have identical FC hardware. Furthermore, the HBA must be equipped with two World Wide Names (WWNs) to facilitate the live-migration process.
In this video, Brien Posey, a Microsoft MVP with two decades of IT experience, walks users through the process of creating a virtualized SAN and then establishing virtual Fibre Channel connectivity from the VM to SAN storage.
About the presenter
Before becoming a freelance technical writer, Brien Posey worked as a CIO for a national chain of hospitals and healthcare facilities. He has also served as a network administrator for some of the nation's largest insurance companies and for the Department of Defense at Fort Knox.
Transcript - Hyper-V 3.0's virtual Fibre Channel feature explained
Greetings, I'm Brien Posey, a long time TechTarget contributor and a ten time Microsoft MVP. In this video, I want to talk about Hyper-V's Virtual Fibre Channel feature. In data centers that use SANs, there are typically going to be certain physical servers that are connected to the SAN through a direct fibre channel link. Now historically, these types of servers have been considered to be poor candidates for virtualization. The reason is simple. The virtualization infrastructure didn't allow virtual machines to communicate directly with a SAN, but all of that changed in Hyper-V 3.0.
Microsoft created a new feature called Virtual Fibre Channel. And the Virtual Fibre Channel feature makes it possible for a virtual machine to connect directly to SAN storage through a virtualized fibre channel adapter. Now, believe it or not, this is actually very easy to set up and I'm going to walk you through it in a few minutes, but it's essentially a two-step process. The first thing that you have to do is to create a virtual SAN, and then once that virtual SAN has been created, then you can establish Virtual Fibre Channel connectivity from a VM to the SAN storage. I'll show you all how that works in a few minutes.
Now, as with anything else in IT, there are some requirements that have to be met. The first requirement is that the virtual machine has to run a compatible guest operating system. For the time being, the only compatible guest operating systems are Windows Server 2008, Windows Server 2008 R2, and Windows Server 2012.
Another requirement is that the host server has to have a compatible host bus adapter, and that adapter has to support N-Port virtualization or NPIV as it's come to be known. Also, the NPIV feature has to be enabled and the adapter has to be connected to an NPIV-compatible SAN. Now one thing to note is that NPIV is, a lot of times, disabled on the physical hardware. So you do need to go in and make sure that the NPIV feature is enabled.
Typically, the manufacturer of your host bus adapter will provide a utility that makes that configuration possible. For example, the server that I'm using for this demo has an Emulex adapter. And Emulex provides a utility called OneCommand Manager that will allow you to go in and enable NPIV. I'll show you how that works as well.
So one of the big questions that always comes up with regard to Virtual Fibre Channel is how does that impact live migration, live migration being the dynamic migration of a running virtual machine from one Hyper-V host to another. Well, live migrations are fully supported with Virtual Fibre Channel, but the requirement is that each host to which a virtual machine could potentially be live migrated has to include duplicate host bus adapters. Also, each host bus adapter has to have two worldwide names and there is a very good reason for that.
The worldwide name is used to establish connectivity to the storage, and you don't want to let go of that connectivity during a live migration. So if you assigned two worldwide names to each host BUS adapter, then what happens is when you perform a live migration, the second node can use the second worldwide name to latch on to the fibre channel storage. Then once that connectivity has been established, then the original node that the virtual machine was running on can release its connectivity safely, and the live migration can continue without ever breaking connectivity to the fibre channel storage.
Now I know that's a lot to take in, so I want to try to make things a little bit clearer with a demo. So what I'm going to do is I'm going to show you how to create a virtual SAN and then I'm going to link a virtual server to that virtual SAN with fibre channel connectivity.
So here we have a Hyper-V host server running Windows Server 2012, and before I go in and show you how to create a virtual SAN, I want to show you how you may end up having to enable NPIV on your host bus adapter. So as I mentioned earlier, I've got an Emulex adapter in this particular server. And Emulex provides a utility which I'm going to launch right here. It's called OneCommand Manager and you can see the utility right here. It's going to take just a second to discover my host bus adapter which it's picked up on. Now the reason for the red X is I don't actually have a SAN. This is a lab environment, but that's okay because we can still work through the demo all the same.
So what I'm going to do is I'm going to select a port and then I'm going to go over to Driver Parameters. You'll notice that we have all of these different parameters that we can set and one of the parameters is enable NPIV. You can see that I've already enabled it, but normally this is disabled by default, so we would have to go in and enable NPIV.
Okay, so I'm going to go ahead and open up the Hyper-V manager. Here, we see a listing for our lab server and I'm going to right-click on this. We have an option here for Virtual SAN Manager which I'm going to go ahead and click on. So this opens up the Virtual SAN Manager dialogue box. And the first thing that I want to show you is the worldwide names.
As you'll recall earlier, I mentioned that we were going to need two worldwide names. Here we can set a range for worldwide names. Generally, going with the defaults is okay, but you can change this if you need to. We also have an option for New Fibre Channel SAN which I'm going to select and click Create. We have to provide a name for the SAN. Generally, it's a good idea to name it something related to your hardware, so I'm just going to call this Emulex. And I'm going to select this check box to accept the worldwide names, and click OK, and our new Virtual Fibre Channel SAN is created.
If I go back into the Virtual SAN Manager, you can see the Emulex just as we created it. So once that's been done, you can actually go in and add Virtual Fibre Channel to a virtual machine. So here we have a virtual machine. I'm just going to right-click on this and go to settings. Incidentally the virtual machine isn't running. It has to be turned off to be able to do this. So the Settings dialogue box is going to open. And what I'm going to do is I'm going to select Add Hardware, and you'll notice here we have a list of the different types of hardware that you can add.
One of the options is Fibre Channel Adapter, so I'm going to go ahead and select that, and click Add. We have a drop down list which will allow us to select a virtual SAN and here's the Emulex virtual SAN that we created earlier. We have an option to edit addresses although going with the defaults is usually okay. So all we have to do now is just click OK and now we have a Virtual Fibre Channel adapter assigned to our virtual machine.
From that point we could go ahead and start the virtual machine and then use that Virtual Fibre Channel adapter to connect to our SAN storage. It's that easy. So that's going to do it for this video. Thank you for tuning in.