Scale-Out File Server (SOFS) is a new feature of Windows Server 2012. This feature provides a file service for application (such as Hyper-V) in an active/active cluster thanks to SMB 3.0. Because this feature uses the Failover Clustering feature, some disks must be connected to each node to convert them in Cluster Share Storage (CSV). These disks can be connected by iSCSI, Fibre Channel, or SAS attached shared JBOD and so using storage spaces. In Scale-Out File Server, more you add nodes, more you have better performance. However you can’t exceed more than 8 nodes. For further information you can view this link.
Because Hyper-V is compatible with SMB 3.0, it can use Scale-Out File Server to store virtual machine. In Virtual Machine Manager 2012R2, it is possible to manage shares of Scale-Out File Server cluster and use them to store Virtual Machine. We will see in this topic how to create the cluster and manage shares in VMM.
Configure Scale-Out File Server
Roles installation
On each node of the cluster, the File Server role and the Failover Clustering feature have to be installed. To launch the installation, open the server manager and click on Add Role and Feature.
If you have centralized the server management as below, select the server where you want to install roles or features.
On the roles screen, select the file server as below.
On the features screen, select Failover Clustering.
Click next until install roles and features.
Cluster failover configuration
Once you have installed File Server role and Failover Clustering feature, open the Failover Cluster Manager. Click on Validate Configuration as below.
Select servers that are part of the SOFS cluster. Now I add two nodes because I want to show you how to add a node after that the cluster is created.
When creating a cluster, it is recommended to run all tests. These tests verify network, storage etc.
Before launch tests, verify your network configuration and your storage. For example my storage is as below on each node. I have three LUNs connected by iSCSI (thanks to Synology NAS :p).
Once all it is ok, launch the test. Anyway if something goes wrong, the test report will tell you.
Below, the failover cluster validation report. All tests are passed successfully. It is because I am on mock-up environment J. In real life, I have never seen this report like that. Anyway, when this report is ok, be sure that Create the now using the validated nodes parameter is checked.
On first Create Cluster Wizard screen, click next.
Type a cluster name and enter a valid IP address.
I don’t check Add all eligible storage to the cluster checkbox because I want add by myself the storage on the cluster.
When you have clicked on next, the cluster is created.
The below warning is normal. It is because I have not configured a quorum witness. I don’t want configure disk witness because I use the new Windows Server 2012 feature called dynamic quorum.
Now that the cluster is created, right click on Disks and select Add Disks to a Cluster.
Select disks that are part of the cluster.
Now that disks are available in the cluster, it is time to convert them to Cluster Shared Volumes (CSV). When they are converted to CSV, they can be used in SOFS.
To finish cluster configuration, open networks part. Rename your networks related to their using and select the right cluster use parameter. Usually, one network has to serve clients.
Add Scale-Out File Server role
Now that cluster is set, right click on roles and select add role.
Select the File Server role.
On File Server Type screen, select Scale-Out File Server for application data.
Choose a name for your client access point. This name will be added in DNS later to connect to share.
Note : As you can see in the above screenshot, a Cluster Name Object (CNO) will be created beside the CNO of the cluster. For example if I create a cluster called Fabrikam-SOFS, a computer object will be created in Active Directory called Fabrikam-SOFS. When you create a SOFS role in a cluster called SOFS01 as above, a CNO will be created beside the object Fabrikam-SOFS. It is very important because the object Fabrikam-SOFS has to have a delegation on the OU where it is to create child item. In this example, it is Fabrikam-SOFS that create the computer object SOFS01 in Active Directory.
Now that SOFS role is added to the cluster, status should report Running. To finish role configuration, an IP address has to be added to resource of SOFS01.
Add an IP address belonging to a network that has client cluster uses.
Add node in cluster if needed
Before configuring VMM with the previous Scale-Out File Server created, I will show you how to add a node to a running cluster. First right click on Nodes in Failover Cluster Manager and select Add Node.
On Select Servers screen, add the server that you want to be part of the cluster.
In a production environment, I recommend you to run all tests before adding a server to a running cluster.
In production environment I recommend you to run all tests to add a node to a running cluster.
My Failover Cluster Validation report informs me that there is no disk witness. As above, I use a dynamic quorum J.
Once you click on finish, you can add the node.
And again, the wizard report me that I have no disk witness. It is because I use Dynamic quorum …
Configure VMM to store Virtual Machine on SOFS
Now that cluster is ready to use, it is time to add some virtual machines to my Scale-Out File Servers. Open the fabric tab and right click on providers to Add Storage Devices.
Select Windows Based file server as the storage provider type.
Provide the name of the Scale-Out File Server role in the cluster. A run As account is needed with appropriate rights.
Select Storage Device and click next.
Select the storage devices to place under management. Note that you can create a classification for this storage.
To add the storage devices to VMM click on finish.
Click on Arrays on fabric, select your storage device and click on Create File Share.
Select the File Server, type a name and select the volume. You can create a classification for this file share. Repeat this operation for each volume that you have.
Now storage volumes are available in VMM.
If you open the cluster failover Manager, you can view the previously created File Share as below.
Now right click on your hosts, select properties and open Storage tab. Click on Add and select file shares that you have created.
Now you can create a Virtual Machine on these shares as below.
As you can see below, the VMTEST01 VM is stored on my Scale-Out File Server.
Test high availability of SOFS
Before testing, the FSLUN01 is owned by VMSOFS03. On FSLUN01, there are my VMTEST01. I will shut down the VMSOFS03 machine to view how VMTEST01 acts.
I have launched the task manager to view if there are some interruption.
Now that VMSOFS03 is shut down, the new FSLUN01 owner is VMSOFS02.
It is impressive, even if the owner of the Cluster Shared Volume (CSV) changes roughly, the VMTEST01 still online. It sounds like magic !
Conclusion
Scale-Out File Server is a new feature of Windows Server 2012. It permits to create Active/Active cluster File Servers for application usage such as Hyper-V. SOFS uses SMB 3.0 technology so this enables Hyper-V to store Virtual Machines on shares of the SOFS. With SOFS, more you add nodes, more you gain performance. However you can’t exceed 8 nodes. As you have seen before on this topic, even if a node is shut down, Virtual Machines keep running. The main advantage of SOFS is that is less expensive than a traditional SAN and fabric storage solution. The best scenario with SOFS is a SAS attached share JBOD with storage spaces. This is a good and cheap storage solution.
