How to Choose a Storage Solution Using BLADE Switches and Fibre Channel Technology

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1 Using BLADE Switches for iscsi Case Study Balance the need for a robust/always-on IT infrastructure while keeping costs low Choosing the right storage technology was a key priority for IT when Blade Network Technologies (BLADE) was established in February While still a division within Nortel, BLADE engineers had already been building, shipping and supporting blade switches for the two largest blade server vendors for the past four years. More products were in the pipeline, and due to release in June So BLADE wasn t the typical startup it had the needs of an established business, but had to build a new datacenter from the ground up. As a newly independent company, BLADE could not afford a moment of downtime customers were expecting their products on time, period. As the IT director planned the network and the data migration from Nortel into new facilities, the business imperative was clear: Balance the need for a robust/always-on IT infrastructure with the startup s need to keep costs low and have it up and running in under a month. BLADE s business profile in February 2006 Privately held technology company Plans to increase from 40 to 80+ employees in first 6 months Revenues in the $50-$100M range Business Operations in U.S.A, Canada, Australia, France, U.K, Germany, Hungary, Scotland, Amsterdam, Vietnam, Malaysia, India, Taiwan, Mexico, & China Mission critical server applications span multiple functions: Engineering (software build, compilation, defect tracking) Finance (accounting AP, AR, GL, etc.) Supply Chain Operations (Product Life Cycle Management) Communications (Blackberry, MS Exchange, VoIP) Disaster Recovery at secondary data center in Canada Choosing a SAN solution: Fibre Channel or iscsi? Since BLADE specializes in developing networking devices for the blade server market, the decision to build the IT infrastructure based on blade servers was a no-brainer. However, looking at the current state of blade servers in today s market, BLADE saw many solutions that assumed reliance on dual technologies Ethernet for LAN, and Fibre Channel for SAN. In fact, most blade servers contain slots for both Ethernet and Fibre Channel switches. BLADE s IT director sat down with a storage expert and took a look at these two technologies. Fibre Channel technology has been around since the late 1980s, and was originally developed to improve connectivity and cable lengths between SCSI devices on super computers. Today Fibre Channel is considered a reliable, congestion-free, and fast method for connecting SANs. However robust the technology has proven itself to be, the IT director and storage expert saw some significant roadblocks to widespread Fibre Channel deployment: Complexity of deployment and upgrades upgrading the initial Fibre Channel deployment as the company grew would require a forklift upgrade of the storage arrays, system downtime High cost of the Fibre Channel equipment Concerns about interoperability amongst Fibre Channel equipment vendors

2 iscsi is a newer SAN networking technology (ratified in 2003) that uses TCP/IP Ethernet for data transfer. The SCSI storage protocol is encapsulated into IP packets for transport through any common Ethernet interface. The simplicity of this technology is that iscsi initiator software on the blade server, paired with iscsi target software on SAN disk storage arrays or tape storage, performs the bulk of the work needed for transporting iscsi data to the SAN. Other Ethernet devices in the network require no specific configuration to handle iscsi traffic, though special consideration for trunked uplinks to the SAN disk array can add performance. Latency was a potential issue with iscsi, as it depended on overall Ethernet network performance, which could vary. The IT director and the storage consultant looked at the following two configuration options: Option 1: Use Ethernet switches to connect to LAN and WAN, and Fibre Channel switches to connect to SAN. They found the following issues with mixed Ethernet/Fibre Channel configuration: An Ethernet and Fibre Channel solution is complex and difficult to maintain, and may require outside consulting. Most in-house IT staff do not have specialized Fibre Channel expertise Servers can t be re-provisioned between web serving to application serving without pulling out the server blades, and swapping NICs and HBAs Local storage on server blades offers poor performance, adds cost, and reduces server reliability Adding on additional Fibre Channel storage arrays could require forklift upgrades, and increase latency as additional storage arrays are daisy chained together Clearly, this was not the right solution for a company building its IT storage infrastructure from scratch.

3 Option 2: Use Ethernet switches to connect to LAN and iscsi SAN So the IT director and the storage expert looked at implementing an all-ethernet solution, using iscsi protocol storage arrays: They saw the following advantages in implementing an iscsi SAN: Solution simplicity: both LAN and SAN run over IP/Ethernet Servers can be dynamically re-provisioned from web serving to application serving (and visa versa) using the included storage management software Disk shelf restriping could be done in a matter of minutes, not days Local storage is consolidated from individual server blades onto a shared disk shelf Virtualization of the disk shelf Local Disk on a server blade required only for iscsi initiator software, thus conserving blade server resources for other applications. Low latency, low CPU utilization on blade server, and minimal bandwidth requirements Block level data replication over the corporate WAN to remote disaster recovery cluster for faster backups Future support for 10Gb Ethernet meant that performance would keep up with the company s growing storage needs They were on to something. Implementing iscsi SANs would make setup and scaling of BLADE s storage arrays both manageable and flexible. The last thing they did was compare cost between Fibre Channel and iscsi. While cost wasn t the determining factor in choosing which technology to implement, the cost savings (detailed below) combined with the manageability and scalability made iscsi the clear winner.

4 Data Center Total Cost of Ownership Table 1 Primary Data Center Configuration, Santa Clara, CA Configuration Ethernet Switches for Ethernet Switches for LAN/ Fibre Channel LAN & SAN Switches for Blade Server chassis + Power Supplies + Switches For LAN and SAN Reason for Cost Delta $36,400 $14,000 FC SAN Switches 10 Server Blades + NICs + HBAs $42,000 $37,600 HBAs 10 TB Storage Arrays $350,000 $120,000 FC Storage Arrays Storage Management Software & Utilities $50,000 $0 (included with Storage Mgt. Software hardware) Installation Cost $10,000 $4,000 Setting up FC arrays takes more time and requires technicians who charge more than Ethernet technicians Net Acquisition Cost After Discount $366,300 $131,700 All of the above Maintenance Costs for 3 years 24*7 Service $128,520 $51,480 Maintenance cost is a % of acquisition cost 3 Year Cost Of Ownership $494,820 $183,180 iscsi is 37% the cost of Fibre Channel Table 2 Disaster Recovery Data Center Configuration: Ottawa, Canada Configuration Cost of Ethernet Cost of Ethernet Reason for Cost Delta Fibre Channel Switches for SAN Blade Server chassis + Power $20,200 $9,000 FC SAN Switches Supplies + Switches For LAN and SAN 5 Server Blades + HBAs $21,000 $17,500 HBAs 10 TB Storage Arrays $262,500 $90,000 FC Storage Arrays Storage Management Software & Utilities $25,000 $0 (included with hardware) Storage Mgt. Software Installation Cost $5,000 $2,000 Setting up FC arrays takes more time and requires technicians who charge more than Ethernet technicians Net Acquisition Cost After Discount $250,275 $90,375 Maintenance Costs for 3 years 24*7 Service $91,110 $34,950 Maintenance cost is a % of acquisition cost 3 Year Cost Of Ownership $341,385 $125,325 iscsi is 37% the cost of Fibre Channel

5 Table 3 Cost of Ownership Summary Cost Item For Both Data Centers Using Ethernet Switches (Primary and for LAN and Fibre Disaster Recovery Sites) Channel Switches for SAN Using Ethernet Savings Over 3 Years as a Result of Using Ethernet Switches & iscsi SAN Acquisition Cost $616,575 $222,075 $394,500 (64% ) 3 year maintenance costs $219,630 $86,430 $133,200 (61%) 3 year Cost of Ownership $836,205 $308,505 $527,700 (63%) Products Used 1. Blade server with single local SCSI drive. A basic blade server installation, this server acts as the host for virtual guest machines. VMWARE server beta (free software) installed iscsi initiator software installed Blade server switches from Blade Network Technologies 2. iscsi Initiator to Equallogic Storage array over multiple trunked Gigabit Ethernet links 3. Equallogic Storage Arrays The virtual machine hosted on the storage array can be moved to another location and booted without reconfiguration. The entire array contents are replicated to the Ottawa Disaster Recovery Center every night greatly reducing recovery time, and ensuring business continuity. Conclusion Implementing a scalable and robust storage solution for a startup the size of BLADE was initially a daunting challenge. Fibre Channel had a reputation for speed and reliability, but was difficult to implement without specialized IT knowledge. There were concerns about day to day management and the cost to scale to a larger storage array. iscsi is built around a well-known technology Ethernet that requires little additional expertise to setup and manage. Virtualization of disk shelf resources allows for efficient reprovisioning of disk resources. And finally, implementing an iscsi storage solution would help the company realize 63% cost savings over three years, compared to a Fibre Channel solution. Our one-person IT department was able to implement the iscsi SAN solution, and build the entire data center, well under the one-month deadline. Now that he s done it once, he s confident he could build it all over again in just one weekend. BLADE NETWORK TECHNOLOGIES: The industry s #1 provider of Ethernet, IP, and application switches for blade server systems. Our products represent a strategic control point in a blade server system. They are the gateway for all traffic directed to and from a blade server system. As a strategic control point, our products have a direct influence on a blade server system s performance, high availability, scalability, manageability, security, and total cost-of-ownership Blade Network Technologies, Inc. All rights reserved. Information in this document is subject to change without notice. Blade Network Technologies assumes no responsibility for any errors that may appear in this document MKT rev1