Overview of SANmelody Disk Server Software

If one server runs out of capacity, soon others will, too…

You have applications spread across multiple machines: mail servers, application servers, database servers, file servers and web servers. What do you do when the database server runs low on disk space, and there’s no more room for expansion? Many will buy another database server. But think twice – if you continue down this path, chances are that you’ll soon have to buy another mail server and file server for the same reason. This isn’t the best way to spend your precious IT budget.

A much more cost-effective solution is available from DataCore Software. Our SANmelody™ shrink-wrap package turns a general purpose server into an expansion “disk server” from which other systems can draw capacity.

The SANmelody disk server approach buys you several unique benefits:

1. Surplus capacity in one disk server is available to any other application that needs it. Unlike a second database server, disks are no longer dedicated to a single application.

2. When the next machine runs out of capacity, you don’t need to buy yet another application-specific server.

3. There’s no need to license and deploy another instance of the application just to address a capacity issue.

Plug and play ease

You can install and configure SANmelody software in just minutes. Your existing servers connect to the expansion disk server using an Ethernet LAN. The additional disk capacity appears as if it comes from internal disk drives. No application changes or application licenses are required to take advantage of the new space.

Ideal for Growth, Extra Security & High Availability

Although data growth is often the primary justification for buying more storage, more and more businesses are acquiring capacity specifically to store online copies of critical data for enhanced security and data availability. A disk server makes it easier to achieve those benefits in a cost-effective manner.

Using a technique called data mirroring or  RAID-1, each time an application saves data to disk, the host operating system transparently stores the data on a local disk volume as well as on a completely separate disk volume provided by the disk server.  Should either volume fail, the other copy takes over immediately as a real-time backup.

Although RAID-1 can be used across two drives inside an application server, it does little good if the server catches fires, gets wet or simply malfunctions.  Having a mirrored copy on a separate disk server, ideally in a different room, increases protection levels and enables you to recover the data by simply connecting a replacement machine to the disk server and reassigning the critical volumes. It’s just like rebooting the original application server after an unexpected outage.

Non-disruptive Expansion

Once in place, DataCore’s SANmelody software also makes future disk expansion non-disruptive. You won’t have to power down an application server to add more disk space. Instead, an intuitive GUI lets you assign disk server capacity to any application over the network with a few mouse clicks. The software maintains a pool of free space which can be carved into logical disks for the next application server that needs storage resources.

Advanced Options When You Need Them

Optional SANmelody software modules address host-independent point-in-time snapshots, redundant disk servers, auto-provisioning of disk space, and remote replication over IP WANs. You can start with the basic package, then upgrade to advanced features when the need arises.

Allocating Virtual Volumes from Physical Capacity

Disk drives come in fixed sizes (18 GB, 36 GB, 120 GB, 300 GB, 500 GB, etc.) that seldom correspond to the actual needs of applications. In many cases, the applications require only a small fraction of the drive’s capacity. Rather than waste the excess space, the storage server administrator can create multiple smaller logical drives that better match application requirements. Each of these logical drives may be assigned specific properties as a unique “virtual volume” to be separately allocated to an application. Doing so effectively improves the utilization of disk space by spreading a large number of logical units across a fixed number of disk drives.

Alternatively, space from several disk drives may be logically concatenated into larger virtual volumes to satisfy applications that require very high capacity LUNs.

A collection of configuration, operation and management modules have been integrated into the Microsoft Management Console (MMC) to make the management of Powered by DataCore™ storage servers simple and intuitive.  

The powerful storage control software runs on top of the Microsoft Windows operating system to provide basic and advanced block storage services over a network or point-to-point connections. Licensed options as well as hardware make-up determine the feature set configured for your environment.

The basic block storage services include:

• Target disk emulation to serve well-behaved virtual disks to popular operating systems (Windows, Unix, Linux, NetWare and MacOS) using iSCSI over Ethernet or Fibre Channel connections

• Disk Initiator to read and write from physical disk drives qualified for the storage server

• Protocol bridging between different host connections and disk drive interfaces (e.g., Fibre Channel host connection accessing disk blocks in Serial ATA drives)

• I/O read and write caching using the Intel server’s RAM as a cache

• Secure LUN allocation (access controls) to prevent unauthorized host access to virtual disks

• Virtual LUNs of different sizes carved out or aggregated from physical disks

• Intuitive administration via Microsoft Management Console (MMC) Snap-ins

• Performance management accessible through Windows built-in Perfmon and storage server-specific performance counters

• Event monitoring of disk resources, cache and I/O channels via Windows built-in Event Viewer and the Windows event log

Additional optional features may be purchased. Contact DataCore Sales for complete information.

Overview