Storage

Serving volumes with the EqualLogic PS200E iSCSI array

In the fifth and final part of the iSCSI project series, Scott Lowe shows you how to create volumes and attach them to your servers for an iSCSI array connected to Windows servers.

TechRepublic's free Storage NetNote newsletter is designed to help you manage the critical data in your enterprise. Automatically sign up today!

In this, the last part in my series about the EqualLogic PS200E iSCSI storage array, I'll go over the steps necessary to create volumes and attach them for use by your servers. While the instructions here are aimed at the PS200E, some of the concepts apply to any iSCSI array connected to Windows servers. For this article, my server operating system is Windows Server 2003 SP1.

If you missed the beginning of the series, check out the first four parts:

Creating a volume: SAN side

As you might expect, in order to attach a volume to a server, you need to create that volume on the SAN first. With the PS200E array, creating a volume and allocating adequate space isn't very hard. First, log in to the array group manager and, under the Getting Started column, click the Create Volume option, as shown in Figure A.

Figure A

Click Create Volume to begin the volume creation wizard.

The volume creation wizard has three steps. In the first step, name your volume and indicate how much space you wish to allocate for data on the new volume. You can also indicate how much disk space to reserve for snapshots of the new volume. In my group, we generally allocate 100 percent reserve (or more, if needed) for snapshots and schedule snapshots every two hours. One hundred percent reserve means that, if we allocate 50 GB for a new volume, which I have done for this example, another 50 GB is reserved for snapshots. Since this was a primary reason for getting the array, I don't consider the space "wasted". See Figure B for a look at this process.

Figure B

Allocate disk reserve space.

We also have a policy of limiting access to volumes only to those servers that need it. Even though we run our operations on a storage network completely separate from the main network, this protects other volumes in the event that a server happens to be compromised. You can see in Figure C that I've limited access to this new volume to a single IP address.

Figure C

Limit access to new volumes.

Finally, you will see a summary page that provides a quick look at the options you've selected for a new volume (Figure D).

Figure D

Believe it or not, that's all that's required to create a new volume on the PS200E. When you're done, the new volume shows up in the main volume list. If you want to perform advanced operations such as establishing a snapshot schedule, you can. I'm going to move on to the server side.

Attaching to a volume: Server side

With the volume created, you need to attach to it from a server. First, with Windows and an iSCSI target in place (the "target" is your new array and volume), you need to download the Microsoft iSCSI initiator. While the latest version is 1.06 (as of this writing), we had problems with this version, and EqualLogic recommended version 1.05a as a replacement. Install the initiator before going any further.

Once the initiator is installed, go to Start | Control Panel | iSCSI Initiator. On the Target Portals properties page, add the IP address for your array. In EqualLogic's case, I need to add the array cluster IP address, as shown in Figure E.

Figure E

Add the iSCSI array to the portals page.

After adding the portal, click the Available Targets tab. Assuming you've properly set up permissions on your new volume, you'll see it on the list of targets at the bottom of the window, designated as Inactive. It's inactive since nothing is yet attached to it. To connect to the target, click the Log On button at the bottom of the window. This results in a logon window that asks a couple of questions (see Figure F). First, do you want to reconnect to this target at boot time? Second, do you want to enable multi-path? I won't be going over multi-path in this article, except to say that it provides a measure of redundancy.

Figure F

Log on to your new volume.

Finally, on the Available Targets tab, click the Bind Volumes button (Figure G). This results in the operating system waiting at boot until iSCSI targets have appeared.

Figure G

Click the Bind Volumes button any time you make changes to a volume configuration.

With your new volume bound, now you need to format it and make it ready for use. Do this in the normal way—through Disk Management at Start | All Programs | Administrative Tools | Computer Management. Since Windows sees the iSCSI target as a new volume, it automatically starts the Initialize And Convert Disk Wizard. During this wizard, you're asked to indicate which new disks you want to initialize and convert. As a note, you do have to initialize your new disk volume, but you should leave it configured as a Basic disk. Don't convert it to Dynamic. When the wizard is done, the disk management tool shows your new volume as unallocated (Figure H).

Figure H

Disk manager shows the new volume as unallocated.

To get the volume ready for use, right-click it and select New Partition from the shortcut menu. When you're done, your new volume will display in My Computer just like any other volume (Figure I) and, on this array, performs extremely well.

Figure I

My Computer displays the new volume.

In the case of the PS200E's manager, some statistics are also kept about your volume, including the length of time it's been up and how much data has been transferred between the server and the volume on the array. Figure J below shows a sample of this information.

Figure J

The manager shows some interesting stats about each volume.

Summary

Overall, you can probably tell I'm very pleased with this array and the ease of use afforded by it. Creating volumes and attaching them couldn't be easier and the unit has performed well beyond my expectations.

Editor's Picks