Fibre Channel over Ethernet (FCoE) has been a much-hyped technology, but adoption rates haven’t yet lived up to the propaganda.
According to Seamus Crehan, an analyst at Dell’Oro Group, only about 10,000 FCoE ports shipped in 2008. While that number is predicted to reach 1 million in 2011, it will still be outgunned by Fibre Channel by a factor of 10 to one.
That said, FCoE isn’t a technology to ignore.
“Since FCoE will be a key data center technology, continued investment in this sector should bode well for the technology,” said Crehan. “New data center technologies and deployment models that have compelling return on investment prospects have resulted in increased investment.”
So what do users need to be doing to prepare for FCoE? Obviously, additional components are needed to set the stage for implementation.
Joel Reich, vice president and general manager of the SAN/iSAN business unit at NetApp (NASDAQ: NTAP) — the company that was first to market with native FCoE in its storage arrays — points out that users need gear to support data center bridging (DCB) as well as the FCoE storage networking protocol. That includes converged network adapters (CNAs) at the host, FCoE-enabled 10Gb Ethernet switches and FCoE-enabled storage at the target.
“One of the advantages of FCoE is that it is not a tunneled protocol,” said Reich. “As a result, FCoE-enabled switches generally support native FC ports as well, so data traffic from FCoE initiators can speak directly to traditional FC storage without having gateways or bridges.”
Made for Server Virtualization
It doesn’t necessarily make sense, though, to turn all applications over to FCoE. IT shops will have to evaluate which applications require the advantages of FCoE networks and which operating systems they will be running on. Server virtualization from the likes of VMware (NYSE: VMW) appears to be a good candidate.
“Server virtualization should be considered, as the increased bandwidth of 10GbE can support high throughput from multiple hosts or VMs,” said Reich. “Additionally, the mobility of virtual servers means that for load balancing and failover, the secondary server should also support the same network protocols in order to ensure the same performance characteristics.”
As FCoE carries similar cost as 8Gb FC today, it should be considered if the bandwidth can be shared and the performance requirements include low latency. For workloads that don’t require heavy I/O, though, Reich feels it doesn’t really make much sense to move to FCoE. For other applications, iSCSI or NAS protocols can be used at a much lower price point.
“If the user believes that some applications will require the higher I/O load and they want to share the infrastructure with the rest of the servers/applications, moving to a unified fabric offers those advantages,” said Reich.
FCoE Steps to Take Now
What many organizations don’t realize is that they can take advantage of the benefits offered by FCoE at the server access layer now, without waiting for end-to-end or multi-hop FCoE.
“Lossless 10 Gigabit Ethernet is a new protocol which is based on the IEEE 802.1 DCB standard,” said Kash Shaikh, product management manager for Data Center Solutions at Cisco Systems (NASDAQ: CSCO). “This new enhanced Ethernet to the server can be seen as the stepping stone to FCoE. 10 Gigabit Ethernet connected to servers greatly reduces the number of server adapters and cables required.”
Today, after all, most organizations have to run parallel network infrastructures for their LANs and Fibre Channel SANs at the server access layer. This requires separate switches, network interface cards (NICs), host bus adapters (HBA) and cabling. Another factor that increases the number of network adapters needed is server virtualization, which requires multiple server adapters to carry traffic out of the servers.
Once the lossless 10 GbE to server is in place, however, it is possible to deploy a unified fabric, which provides the flexibility to run either LAN, Fibre Channel storage with FCoE, or IP-based storage such as NAS or iSCSI, or a combination of these technologies.
According to Shaikh, the first step is to deploy 10GbE at the access layer between servers and network access switches. CNAs that combine the functionality of NICs and HBAs in a single adaptor can be deployed to simplify implementation and reduce the number of adaptors, cables and switch ports while carrying FC and Ethernet traffic on a single link.
“Converged Ethernet and SAN networks with FCoE at the access can reduce upfront capital costs by up to 50 percent,” said Shaikh. “For a new 1 MW 10,000-square-foot data center, using FCoE and a unified fabric can save 40 percent in cabling costs.”
However, Alexander Nier, product manager for DataCore Software, cautions that an understanding of the underlying technology is a must or implementation headaches will crop up.
“Don’t confuse FCoE with a freshly paved road where everything goes better just because it’s new,” said Nier. “FCoE is a complementary technology rather than a replacement for existing products. The main prep work is to understand if somebody may or may not benefit from using FCoE.”
To his mind, if you are a happy camper today, there is probably no need to switch gear. As FCoE is still in the early stages of adoption, he wouldn’t encourage anyone to switch if the technology they have in place is satisfactory. FCoE’s primary intention, after all, is to consolidate back-end cabling by using the same physical media (Ethernet cable) for multiple transportation streams in parallel.
“If the back-end cabling of your server racks looks like a mess, and each server has a bunch of fiber optic and network cables connected to it, you’re probably a good candidate,” said Nier.
Start with a Pilot
Companies can, of course, purchase and deploy FCoE server I/O consolidation products today. But from business and operational perspectives, it is probably best to look before you leap. The evaluation process should include the identification of specific applications and servers that benefit from the move to FCoE, and preparing the IT department with suitable technical skills to deploy and manage the new configurations. In most cases, a pilot program is recommended.
“Work with a vendor with experience in both storage and networking technologies, because FCoE requires skills in both areas,” said Ahmad Zamer, senior product marketing manager at Brocade (NASDAQ: BRCD).
Zamer warns against setting overblown expectations; few technologies deliver all the promised benefits in first-generation products. It may be best, therefore, to begin with lower-level applications and move upward as the technology demonstrates its maturity. Accordingly, Brocade suggests FCoE when adding new servers and expanding data centers rather than converting existing infrastructures. Zamer said FCoE is best suited for new servers in Windows and Linux environments where virtualized tier 3 and some tier 2 applications are running.
“Demanding applications that are found on database servers are best served by more suited technologies such as FC,” he said. “FCoE will complement FC in the data center, where FC will continue to be the technology of choice for demanding tier 1 applications.”
Follow Enterprise Storage Forum on Twitter