What are the applications for IP Storage?

Case studies illustrate how IP Storage protocols such as iSCSI, FCIP, and iFCP provide more-affordable storage connectivity options.

By David Dale

Over the past year, IT professionals have shown increasing interest in IP Storage solutions. A year ago, it was mainly early adopters, but today you can find IP Storage deployments in many mainstream IT production environments.

The rate of deployment has been accelerating over the last year, despite the absence of some major storage vendors. This pace will continue to accelerate into 2005, as the remaining storage vendors bring IP Storage solutions to market.

In this article, a companion piece to an earlier InfoStor article that discussed where IP Storage fits in the IT infrastructure (see "Who's using IP Storage, and why?" May 2004, p. 18), we examine what companies are using IP Storage today, the primary reasons for deployment, and the platforms and applications supported. As in the previous article, we'll use real-life examples of production deployments by way of illustration.

IP Storage protocols/topologies

First, a review of the protocols and typical deployment topologies is necessary.

The term "IP Storage" is generally used to refer to a SAN solution that utilizes standard Ethernet connectivity in some way. These solutions typically fall into one of two categories: those that use an Ethernet link to interconnect Fibre Channel SAN environments via gateways, and those where a SAN is built using Gigabit Ethernet infrastructure instead of Fibre Channel.

The benefits shared by both of these solutions derive from the cost, flexibility, reliability, distance, and ease-of-management advantages associated with standard Ethernet networking.

Interconnecting FC SANs

Two IP Storage bridging protocols (FCIP and iFCP) are available to provide the basis for interconnecting existing Fibre Channel SAN environments. The use of IP networks here is typically to overcome the distance limitations of Fibre Channel; to provide lower-cost solutions than using proprietary protocols over private fiber links; and to enable remote data-protection and disaster-recovery solutions.

FCIP is a TCP/IP-based tunneling protocol designed to transparently provide point-to-point connections between geographically distributed Fibre Channel SANs using FCIP gateways to connect to an IP network. FCIP is well-suited to providing connectivity to remote SANs for backup and restore, or to remote data replication applications.

Figure 1: IP Storage protocols such as FCIP and iFCP can be used to connect Fibre Channel SANs over MANs and WANs.
Click here to enlarge image

iFCP is a TCP/IP-based protocol for interconnecting storage devices or Fibre Channel SANs using an IP infrastructure. iFCP solutions consist of Fibre Channel end-points connected to an IP network by means of iFCP gateways. iFCP is particularly well-suited to providing reliable transport of storage data between SAN domains via TCP/IP LAN, MAN, or WAN infrastructure. Figure 1 illustrates the general form of these topologies.

IP-native SANs

In contrast, the iSCSI protocol enables the creation of complete SAN solutions based on a Gigabit Ethernet, instead of Fibre Channel, network infrastructure. iSCSI is simply the combination of SCSI block storage commands running over a TCP/IP transport.

iSCSI SAN solutions (often called IP SANs) consist of iSCSI initiators (software driver or adapter) in application servers connected to iSCSI storage systems by means of standard Gigabit Ethernet switches and cables. Figure 2 on p. 28 shows a typical IP SAN environment using iSCSI.

Figure 2: iSCSI enables IP-native SANs based on Gigabit Ethernet.
Click here to enlarge image

iSCSI is particularly interesting as a SAN alternative to direct-attached storage (DAS) in environments where simplicity, flexibility, and price/performance are critical IT decision factors, as well as for cost-effective and efficient backup and disaster-recovery solutions.

Taken together, IP Storage solutions broaden the options available to IT managers to address the cost, availability, performance, and manageability issues caused by continual data growth, and to accelerate their transition from a direct-attached to a networked storage model, as we will see from our deployment examples.

IP SAN deployments

IP SANs are deployed for the same reasons that Fibre Channel SANs are typically deployed as an alternative to DAS. According to International Data Corp. (IDC), the top reasons for deploying SANs are the following:

  • Backup (46%)
  • Storage consolidation (40%)
  • Satisfy ongoing demands for additional capacity (37%)
  • Performance (31%)
  • Disaster recovery (27%)
  • New project or application deployment (23%).

Our first two iSCSI case studies are examples of this. Backup and storage consolidation in the face of rapid data growth are the primary reasons for considering an IP SAN, followed by the intention to implement an affordable disaster-recovery solution.

Ecker Enterprises

Ecker Enterprises Inc., one of the largest specialty subcontractors in the US, deployed an IP SAN using the StoneFly Backup Advantage solution.

Faced with rapid data growth, which strained DAS resources and created performance bottlenecks, Ecker sought an affordable solution for consolidating storage while improving what had become a slow and unreliable method for handling data backup and recovery. StoneFly Backup Advantage (SBA), which combines StoneFly Network's Storage Concentrator i3000 with backup-and-recovery software from CommVault Systems, offers cost-effective "LAN-free" disk-to-disk backup, storage provisioning, and replication tailored for IP SANs.

As a result of the deployment, Ecker has increased the speed and reliability of disk-to-disk-to-tape backups while reducing overall costs. Complete backups went from a full-day process to less than one hour. Data restores are completed in about a minute. Ecker is now in the process of deploying StoneFly's Replicator mirroring software, which comes bundled with SBA, to increase performance and near-term data availability by replicating backups to a remote IP SAN.

Johnson Health Network

Johnson Health Network (JHN) is a regional healthcare center located in Stafford and Enfield, CT. The company's data center is located at Johnson Memorial Hospital in Stafford, with domain controllers at the off-site locations. The IT infrastructure includes Windows 2000, 2003, and NT 4.0 servers; PCs from Windows 95 through XP; and Citrix profiles.

JHN replaced a small Fibre Channel SAN with an iSCSI-based PeerStorage Array 100E from EqualLogic in part because of its ease of use, ability to self-manage, easy integration into the company's existing network, and lower cost. JHN uses the PeerStorage array to support its file servers and e-mail servers and plans to set up clustered servers for the Citrix profiles next.

But the bulk of the capacity is used as a virtual tape library for backup. By backing up all files to the iSCSI array, JHN improved backup time and minimized network traffic. Keeping online backups speeds recovery and allows JHN to send data off to tape whenever necessary.

In the future, JHN plans to include more PeerStorage arrays for additional data-center capacity plus replication at the company's nearby Enfield location.

More applications for IP SANs

iSCSI is a standard SCSI block-level protocol, so it works transparently with all applications. In addition, the performance and bandwidth provided by iSCSI over Gigabit Ethernet make it adequate for the vast majority of applications running today. So the question comes down to, "What kind of server environment does iSCSI best fit, and what applications usually run there?"

Today, iSCSI storage solutions are being deployed primarily in environments dominated by midrange and low-end servers. These classes of servers are most likely to be Intel-architecture servers running Windows, NetWare, or Linux, although solutions for small RISC servers running Unix are now starting to emerge. The applications here are typically business-critical at the departmental level, though there are mission-critical applications for smaller enterprises on these servers.

The most popular applications in these environments are Microsoft Exchange, SQL Server, and business applications running on top of smaller Oracle or IBM DB2 databases. Messaging, Web, e-commerce, and some technical applications are also a good fit for iSCSI. Finally, users with homegrown applications running on smaller servers with internal or DAS are finding iSCSI a viable storage consolidation solution, since the migration to an IP SAN is affordable and relatively painless.

The following three examples are typical of these types of environments. These examples also illustrate that IP SANs are not just about affordable storage. Customers are finding sophisticated data management solutions to not only consolidate and protect their data locally, but also to integrate it with their global data assets in multi-tier storage architectures.

DSL Extreme

Based in Los Angeles, DSL Extreme is one of the nation's fastest-growing ISPs, supporting thousands of customers and serving more than 20 major metropolitan areas throughout the US.

To ensure its Microsoft Exchange servers could scale, DSL Extreme needed to transition from its DAS environment to networked storage. The company implemented an IP SAN using Alacritech's SES1001 iSCSI Accelerators on the server side to offload storage I/O processing, ensure resiliency, and help speed iSCSI data to and from the iSCSI storage system-a Network Appliance FAS270.

The combined Alacritech and NetApp iSCSI solution enables the mail servers to move 2000 files per second, or about 2.5 million customer e-mails a day, with no delay on the customer side. By implementing an IP SAN solution for its Exchange application, DSL Extreme guaranteed global mail availability and fast response times to its users and accomplished full system backups without downtime by using snapshots, all while maintaining maximum system availability and performance.

American Tower

American Tower, an independent owner, operator, and developer of wireless communications towers with approximately 15,000 sites in the US, Mexico, and Brazil, leases tower capacity to a variety of cell phone companies. American Tower installed an IP SAN from LeftHand Networks early this year to store data related to the towers they own and to protect that data by replicating it between the company's Boston and Atlanta facilities.

American Tower uses a homegrown application based on Microsoft SQL Server and .NET to manage its tower data. The primary data store is maintained at the company's Southborough, MA, data center. According to IT manager Rob Sherman, "The IP solution integrated well with our Windows servers. The storage appears just like a locally attached disk."

Each day at noon and at midnight, the data is replicated to the Atlanta data center using a combined snapshot/replication feature that copies the data over the IP network.

"The fact that the solution fit well into our existing IP network contributed significantly to keeping our acquisition costs down," says Sherman. American Tower is currently using an "auto-grow" feature that automates the process of resizing the primary storage volumes as the number of snapshots grows. Only data that has changed since the last replication is copied over the IP network to Atlanta, maximizing transmission efficiency.

"We love the simplicity of an IP-based solution," says Sherman. "It's easy to manage with minimal, if any, maintenance. The IP SAN has been up and running for six months, and we haven't had to touch it."


Mazda North American Operations is responsible for marketing, sales, and service operations in the US for Japan-based Mazda Motor Corp. Its customers include 700 dealerships throughout the US. Mazda is exploring new, data-intensive initiatives to improve efficiency and strengthen dealer relationships. Performance and availability are critical to the success of these projects, but Mazda's proliferating DAS environment was unable to keep pace. The company also recognized that an unexpected catastrophe could result in irreversible data loss.

"We had secretaries doing tape backups," recalls Mark Williams, IT project lead, "and they would do the backups at different times, so we were never exactly sure what data had been backed up."

The solution involved replacing Mazda's networked storage, DAS, and tape backup systems with an IP-based three-tiered storage infrastructure

At Mazda's US headquarters, Network Appliance FAS storage systems support mission-critical SQL Server databases using iSCSI while simultaneously supporting Exchange and Mazda's Epiphany marketing program. NetApp SnapMirror software replicates data on the FAS systems to a NetApp NearStore system that provides disk-based backup for online disaster recovery. In each of seven regional offices, storage for Windows servers was consolidated on entry-level NetApp storage systems. Mazda creates snapshot copies of incremental data on an hourly basis, and NetApp SnapVault software is used daily to copy this to the NearStore system at headquarters. Centralized backup information on the NearStore system is sent to tape for off-site archival.

Interconnecting Fibre Channel SANs

IP-native SANs are only part of the IP Storage story. As mentioned, IP Storage solutions play an important part in complementing and extending existing Fibre Channel SAN environments.

The final two case studies illustrate how FCIP and iFCP gateways can be used to enable distance replication and disaster recovery between remote Fibre Channel SANs.

Thompson Hine

Thompson Hine, an Ohio-based law firm, uses a FalconStor IP Storage solution to interconnect the Fibre Channel SANs in its primary and secondary data centers. The firm can now effectively replicate data overnight to its secondary data center through the company's T1 connection. Thompson Hine is utilizing its existing production WAN infrastructure for the nightly replication of data from its satellite offices, eliminating any increase in communication costs since a dedicated replication connection is not needed.

FalconStor IPStor servers are configured in an active-active fail-over mode at the primary data center for high availability, providing replication, storage consolidation, and snapshot services for Oracle and Exchange 2000 databases, ensuring point-in-time consistency and transactional integrity during backups.

IPStor's ability to mirror between dissimilar storage subsystems enabled the law firm to mirror its main data center to a lower-cost, higher-capacity ATA RAID system, providing seamless fail-over and redundancy. The ATA RAID system is also being used as an IPStor NAS share for large desktop PC images, while being considered for document imaging and archiving in the near future.

The introduction of the IP Storage solution into Thompson Hine's IT environment helped the firm avoid additional expenses, leverage its existing infrastructure, and realize an immediate return on investment through more-efficient storage utilization.

Honda Motor Europe

Honda's products include passenger cars, motorcycles, marine engines, lawnmowers, and technology for Formula One racing and jet aero-engines. Honda Motor Europe's annual sales are about $2 billion.

New corporate governance requirements meant that business continuity was a high priority for Honda Motor Europe, which needed the ability to recover from a disaster to support its dealer network where the increased use of images and multimedia was driving data growth 30% annually. These requirements stretched the company's DAS architecture.

To better use its storage resources and scale its infrastructure, Honda Motor Europe replaced its DAS with Fibre Channel SANs at its UK headquarters in Langley and at its disaster-recovery site in Poyle, using McData fabric switches in both locations.

It also deployed a McData IPS 3300 Internetworking Switch at each data center to replicate data to the disaster-recovery site over a WAN link. These switches communicate using the iFCP protocol; standard features include data compression, rate shaping, and "fast-write" performance, plus the ability to isolate faults between the two SAN fabrics. This solution enables the company to recover as quickly as possible with minimal data loss.


As these case studies illustrate, IP Storage is becoming a mainstream network storage solution. IP Storage solutions are available from a number of vendors to extend and complement existing networked-storage environments.

The emergence of IP-native SAN solutions means that IT professionals now have SAN storage solutions for a much broader range of environments at a broader range of price points. Storage consolidation, simplified data protection, affordable disaster recovery, and improved data management are the major focus of IP Storage deployments, and business applications running on midrange and smaller servers are today's sweet spot.

The pace at which IP Storage moves into the mainstream will accelerate as the remaining large storage vendors release IP Storage products over the coming months. Now IT managers can take advantage of new networked-storage opportunities and use IP Storage solutions to address some of their most critical data-management pain points.

David Dale is chair of the Storage Networking Industry Association's IP Storage Forum. For more information, go to www.ipstorage.org.


This article is based on case studies of customer deployments of IP Storage solutions supplied by the following SNIA IP Storage Forum member companies: Alacritech, EqualLogic, FalconStor, LeftHand Networks, McData, Network Appliance, and StoneFly Networks.

This article was originally published on December 01, 2004