Configuring SAN Volumes for Windows Virtual Server

You can either use tools provided by your SAN vendor to provision SAN volumes or use Microsoft Storage Manager for SANs. SMfS simplifies and standardizes the process of performing storage subsystem operations, but it doesn’t entirely replace functionality available in the vendor’s tools, such as configuring replication, snapshots, and thin provisioning. As I discuss in the main article, you need to ensure that the appropriate Virtual Disk Service (VDS) provider for your hardware is installed.
 
Open SMfS from the Control Panel Administrative Tools applet, and click the Subsystems icon in the left pane. If you see your hardware under the Subsystems node in SMfS, your VDS hardware provider is loaded. You can then create iSCSI targets, configure security for those targets, create Logical Unit Numbers (LUNs), and start using your SAN storage. (In an iSCSI SAN environment, a target is an IP address that hosts can use to connect to a storage system and a LUN is an identifier for a particular chunk of storage. A portal is a combination of the IP address and TCP port—typically, port 3260 by default.)
 
To create a target on the iSCSI subsystem, select LUN Management and click Manage iSCSI targets. In the Manage iSCSI Targets dialog box, select the subsystem for which you’ll create the target, then click Add. In the Add Target dialog box, type a descriptive name for the target that will help you to distinguish it from other targets in the in Target Friendly Name field. In the Select portals to enable for this target field, select the check box next to the appropriate IP address for your storage subsystem, then click OK. You can repeat this process for as many targets as you want to add.
 
You should apply one of the several available iSCSI security options—one-way CHAP, mutual CHAP, or IPsec. To do so, click the LUN Management node and choose the ManageiSCSI Security option in the Actions pane. I won’t get into the specifics of choosing an appropriate security level for your environment, but to prevent unauthorized and potentially damaging access to your SAN, you need to at least employ one-way CHAP. To configure one-way CHAP for one or more targets in SMS, click Manage iSCSI Security in the Actions pane and click Set Secret. Type and confirm the target CHAP secret. If you’ll be connecting to the targets from the system you’re working on, selecting the Remember secret on local initiator option will configure your local iSCSI initiator with the CHAP secret. After setting up one or more targets, you can use SMfS to create a LUN and assign it to a target. To do so, simply select Create LUN to launch the Create a LUN Wizard in SMfS.
 
After you’ve configured targets and logged on to them, each target will show up in the Disk Management utility. Each volume must first be initialized, just as if you added new disks to your system. Microsoft doesn’t support dynamic disk volumes on iSCSI-connected storage, so be sure to initialize all SAN volumes as basic disks. You can then create and format partitions. After completing these steps, you should have some fresh volumes that are partitioned and formatted, and you can begin migrating data or creating VMs on those stores. However, before you get carried away, you need to perform a few more steps so that your volumes don’t disappear the next time your server reboots and so that any file shares you create that rely on those volumes also survive the reboot. After you follow these steps, the SAN volumes on the Windows server will be ready for production.
 
1. Make the Server service dependent on the iSCSI Initiator service so that all volumes are online when they’re needed by one or more components of the OS. To do this, use the Service Control (SC) utility from a command prompt. The command

sc config LanManServer depend= MSiSCSI

tells the system not to start the Server service until the iSCSI service has successfully started. You can verify that your command succeeded by viewing the properties of the Server service. On the Dependencies tab, you should see the new dependency you just configured.
 
2. Make the logged on targets persistent in the iSCSI initiator. To do so, open the Microsoft iSCSI Initiator from the Start menu and go to the Persistent Targets tab. Your goal is to make sure all SAN targets that you want to be reconnected after a reboot appear in the window on that tab. You can set the persistent flag only while logging on to a target. So, if you’re already logged onto a target, you must log off, then specify the persistent flag when logging back on by selecting the Automatically restore this connection when the system boots check box. Logging off from a target can be a bit difficult depending on what the system or applications are doing with the LUN assigned to the target. You can try logging off via the iSCSI Initiator tool or SMfS, and you might need to try the logoff a few times before you succeed. If all else fails, a reboot will release the target.
 
3. Bind your persistent targets in the iSCSI Initiator to their appropriate drive letter or mount point. To do so, go to the iSCSI Initiator’s Bound Volumes/Devices tab and, after verifying that all your SAN volumes are listed, click Bind All.