Expert Video: Brien Posey on Windows Server 2012 iSCSI featuresDate: Jan 16, 2013
In the first webcast in a series of five, Microsoft MVP Brien Posey discusses the impact of the new Windows Server 2012 iSCSI Target software functionality. Watch the video above to learn how to install the iSCSI target, create an iSCSI virtual disk and use iSCSI for failover clustering. Read some of Posey's comments below to learn practical tips for getting the most out of Windows Server 2012.
iSCSI isn't anything new to Windows. Windows has supported the use of iSCSI for quite some time, but prior to the release of Windows Server 2012, Windows Server has never had its own native iSCSI Target software.
The iSCSI Target software in Windows Server 2012 is natively included, but installing it is a little bit tricky. It's not that there's anything difficult about installing the iSCSI Target; it's just that the installation option is kind of hidden.
What you have to do to install the iSCSI Target is to open Server Manager and choose the option to install roles and features. When you get to the Server Role screen, the "iSCSI" option is actually hidden beneath the "file and storage services" option.
View the rest of Brien Posey's WS 2012 tip series:
Video tip 2: Native data deduplication capabilities
Video tip 3: Resilient File System (ReFS)
Video tip 4: Windows Storage Spaces
Video tip 5: Offloaded Data Transfer (ODX)
If you expand this out and then expand "file and SCSI use services," you'll notice that down at the very bottom we have "iSCSI Target software" as an option. So we just select that check box, click "next" a few times, and then that installs the iSCSI Target software.
Once the iSCSI Target software has been installed, you'll do all of your iSCSI configuration directly through Server Manager. You can see an excerpt from Server Manager on this slide, and you'll notice a listing for "file and storage services." If you click on this link, it will take you to the place you need to go to configure iSCSI.
Here we have the "file and storage services" screen. It's a little bit covered up, but you can see that we have a tab for iSCSI. This is where we go to configure our iSCSI Target.
This is a two-step process. The first thing we have to do is create an iSCSI virtual disk. This is just a virtual hard disk file. You can see it has the .vhd extension, indicating it's a virtual hard disk. I've already created a virtual hard disk for demonstration purposes.
Go to "tasks," and there's an option to create an iSCSI virtual hard disk. Once that virtual hard disk has been created, the next step in the configuration process is to build an iSCSI Target that's linked to that virtual hard disk. We've actually got an iSCSI initiator that's connected to that target, which we can see by the connected status.
In case you're a little curious what the virtual hard disk used by the iSCSI Target really looks like, I want to go ahead and show you. The File Explorer has two drives: a C drive and an F drive. The F drive is a physical drive on this server, and you'll notice that it's just about out of space. The reason for that is because I created a virtual hard disk on this drive that used almost all of the available space, and I did that intentionally.
You'll notice there is a folder called "iSCSI virtual disks." Within that virtual disk, we have my iSCSI VD. I actually named the virtual hard disk file; this is the name I assigned to you, and you'll notice that this is just a regular .vhd file, and we can see that the type is our disk image file, and we can see the size of the file.
We can't go in and mount this the way we normally could with a virtual hard disk, but the only reason we can't do that is because, at least in this case, that virtual hard disk is already in use.
At the very beginning of this presentation, I talked about some of the things that iSCSI was good for, and one of the things that I mentioned was failover clustering. Shared storage isn't technically required for failover clustering anymore; it was in the previous version of Windows Server, but it's not now. Even though it is no longer required, Microsoft does recommend that you use shared storage if at all possible.
If you want to use iSCSI for failover clustering, you need to create a cluster shared volume. The first thing that you are going to do is to create an iSCSI virtual disk and an iSCSI Target, just as I showed you a few minutes ago.
After you have done that, what you are going to do is authorize each cluster node's IQN on the iSCSI Target, and then once that's been done, you're going to attach the first cluster node to the iSCSI target using that node's iSCSI initiator. When you make that connection, there is an option to enable "multiple path"; it is extremely important that you enable this option by selecting the check box, because otherwise the other cluster nodes aren't going to be able to connect to your iSCSI Target.
Once you have made that initial connection from your first cluster node, then you just go ahead and repeat the process with your remaining cluster nodes. Once that's been done, then you go on to one of your cluster nodes and initialize the iSCSI disk on that cluster node and bring it online. At that point, the last step in the process is to use the failover cluster manager to designate the iSCSI Target as cluster storage.
About the presenter:
Brien Posey is a regular SearchStorage.com contributor and a Microsoft MVP with two decades of IT experience. Before becoming a freelance technical writer, Brien was CIO for a national chain of hospitals and health care facilities. He also served as a network administrator for some of the nation's largest insurance companies and for the Department of Defense at Fort Knox.