Gartner exposes FCoE "myths"

March 19, 2010 – Much of the talk about the demise of Fibre Channel relates to its prospects as a disk drive interface, where it is rapidly losing ground against SAS and SATA drives. But Fibre Channel as a SAN interconnect is still going strong, despite rapid growth in the NAS and iSCSI markets.

In fact, the Fibre Channel SAN market racked up record sequential revenue growth in the fourth quarter of 2009 – more than 15% quarter-over-quarter, according to the Dell’Oro Group market research firm. And the leading players in the Fibre Channel switch and HBA markets – Brocade, Cisco, Emulex and QLogic – turned in strong sequential performance numbers. Q4 2009 results were strong enough to put Fibre Channel revenues close to par with the record results recorded in late 2008.

Dell’Oro vice president Seamus Crehan attributes the strong performance to “improving economic conditions, overzealous budget cuts during the first half of 2009, government stimulus, alleviated supply constraints . . . and the server upgrade cycle that started in the second quarter of 2009.”

However, the future success of Fibre Channel as a SAN interconnect rests largely on the success of the Fibre Channel over Ethernet (FCoE) protocol.

InfoStor readers are by now very familiar with the potential benefits of FCoE and converged (LAN + SAN) networks (see Related Articles links at the end of this post). But a recent report from Gartner suggests that the concept has been over-hyped and that, in fact, many of the key arguments in favor of converged networks are flawed.

Here’s the Gartner press release, which includes a link to the full report (10 pages, $195):

Gartner Says Don't Assume That a Single Converged Data Center Network Is More Efficient Than Two Well-Designed Separate Networks

Converge All Data Center Traffic to a Single Technology, Not a Single Network

STAMFORD, Conn., March 16, 2010 — The notion that a single converged data center network makes for fewer switches and ports, resulting in a simpler network consuming less power and cooling, is flawed, according to Gartner, Inc. Gartner research shows that a converged data center network requires more switches and ports, is more complex to manage and consumes more power and cooling than two well-designed separate networks.

"The industry is abuzz with the promise of a single converged network infrastructure, this time in the data center core," said Joe Skorupa, research vice president at Gartner. "Alternatively described as Fibre Channel over Ethernet (FCoE), Data Center Ethernet (DCE), or more precisely, Data Center Bridging (DCB), this latest set of developments hopes to succeed where InfiniBand failed in its bid to unify computing, networking and storage networks."

"The promise that a single converged data center network would require fewer switches and ports doesn't stand up to scrutiny," Mr. Skorupa said. "This is because as networks grow beyond the capacity of a single switch, ports must be dedicated to interconnecting switches. In large mesh networks, entire switches do nothing but connect switches to one another. As a result, a single converged network actually uses more ports than a separate local area network (LAN) and storage area network (SAN). Additionally, since more equipment is required, maintenance and support costs are unlikely to be reduced."

In addition to the financial barriers to the success of a single converged data center network, Gartner also believes that there are significant design and management issues to be addressed. When two networks are overlaid on a single infrastructure, complexity increases significantly. As traffic shares ports, line cards and inter-switch links, avoiding congestion (hot spots) becomes extremely difficult. Mr. Skorupa said that over time, emerging standards, such as Transparent Interconnection of Lots of Links (TRILL) may make it easier to avoid these hot spots, but mature, standards-compliant implementations are at least two to three years away.

Debugging problems in the converged network are also more difficult since interactions between the LAN and SAN traffic can make root cause analysis more difficult. Since many problems are transient in nature, events must be correlated across the two virtual networks, increasing complexity. Should an outage be required for solving a problem or simply for performing maintenance, a downtime window that is acceptable for both environments may be required. This increases complexity and may increase cost, as well.

"It's clear that the barriers to a single network range from a dearth of available products and the price premium charged for those products to the requirement to "forklift upgrade" your entire network to long-standing organizational conflicts," said Mr. Skorupa. "However, while the promise that a unified fabric will require fewer switches and ports, resulting in a simpler network that consumes less power and cooling, may go unfulfilled, that doesn't mean that enterprises should forgo the benefits of a unified network technology."

Mr. Skorupa said that there is clear benefit in standardizing on a single technology for all data center networking if that technology adequately supports the needs of applications. This will simplify acquisition, training and sparing. However, settling on a single technology does not require that the networks be combined. Design, operations and troubleshooting is much easier with two separate networks, and it may also cost less to build two separate networks.

Additional information is available in the report "Myth: A Single FCoE Data Center Network = Fewer Ports, Less Complexity and Lower Costs."

Related articles from InfoStor:

Guidelines for FCoE deployment

The shift to FCoE is underway

Is FCoE the future of data center networks?

For a cogent rebuttal to Gartner's arguments, see "Gartner on FCoE: Whoa There, Sparky"

Virtual server SANs: FC vs. iSCSI vs. NAS

February 8, 2010 – In the beginning, most virtual server environments relied on either Fibre Channel SANs or direct-attached storage (DAS). As the virtual environments grew, end users quickly found out that DAS wasn’t going to cut it. Fibre Channel remained king for awhile (and still is), but iSCSI – and NAS – appear to be coming on strong.

In mid-2009, we polled infostor.com visitors regarding what type of storage network protocol they were using in their virtual server environments:

The question: “If you have virtual servers, what is your primary storage configuration? (check one)”

The results: 53% cited Fibre Channel SAN; 28% iSCSI SAN; 10% NAS; and 9% DAS.

A recent report from Forrester Consulting, based on a survey commissioned by Dell (no doubt the EqualLogic crew), suggests that iSCSI – as well as NAS -- is narrowing the gap with Fibre Channel. Forrester surveyed 200 IT storage decision-makers.

The question: “What storage network protocol(s) are you using (or plan to use) for your virtual server environment? (select all that apply)”

The results: 59% Fibre Channel, 57% iSCSI, and 52% NFS [NAS]. Almost a dead heat. (3% of the respondents are using non-networked storage; e.g., DAS.)

In addition to the impressive showing of both iSCSI and NAS, a key conclusion here is that end users are obviously using a mix of storage protocols in their virtual server environments.

There was, however, one seeming inexplicable anomaly in the results to that Forrester survey question: 33% cited FCoE. I’m at a loss to explain that, but here’s the explanation from the report’s authors:

“FCoE interest appears very high. There may well be some confusion regarding the adoption of FCoE, as anecdotal evidence suggests that the 34% current usage number [referring to another question] is very high for this emerging protocol. Products are just now coming onto the market and are usable only for the server side of storage networking, aggregating traffic in top-of-rack and edge switches. The reality here is likely that respondents have interest in or plans to move forward with FCoE, but have not yet implemented FCoE in such high numbers.

Confusion with FCIP, used to carry FC traffic over the WAN for distance replication, may also be increasing the adoption rates reported in this survey.

Another area of confusion relates to the adoption of 10GbE. Respondents who stated that they currently have FCoE in place in the quantitative survey revealed in interviews that they actually have 10GbE for file data traffic but are not using FCoE equipment. Suffice it to say that interest in FCoE is high at this point, but confusion about what really constitutes FCoE is clouding the adoption picture.”

Back to Fibre Channel, iSCSI and NAS: Not surprisingly, use of these protocols in virtual server environments varies by the size of the organization. For example, 70% of large enterprises (1,000 or more employees) cited Fibre Channel, compared to 50% of the SMBs.

66% of the SMBs cited iSCSI, compared to 47% of the large enterprises. And 49% of the SMBs cited NFS, compared to 57% of large enterprises.

The full report is posted on Dell’s site: “Benefits Of SAN/LAN Convergence: Evaluating Interest In And Readiness For Unified Fabric,” is posted on Dell’s site.

If you’re struggling with the storage challenges associated with rapidly growing virtual server environments, consider attending our Webcast, “Managing VM Sprawl and Reducing Costs with Disk Archiving,” tomorrow (Tuesday), February 9 at 10:00 PST, 1:00 EST.

You can get a description of the Webcast and register HERE.

Emulex, QLogic jockey for position

November 16, 2009 – The Dell’Oro Group market research firm recently released its Q3 2009 SAN Report, which includes market share figures for SAN product categories such as Fibre Channel HBAs and converged network adapters (CNAs) based on the Fibre Channel over Ethernet (FCoE) standard.

As they always do, Emulex and QLogic almost immediately released press releases claiming market share gains and/or leadership. Nice piece of PR one-upmanship. In each case, the companies just emphasize the slice of those markets that they happen to have good news about.

For example, Emulex reported that it is the leader in FCoE CNAs, according to the Dell’Oro report, with revenue growth of 160% over the previous quarter. The company also highlighted the fact that it gained 4% market share in the 8Gbps Fibre Channel HBA market.

QLogic reported that it’s the leader in the overall (4Gbps and 8Gbps) Fibre Channel HBA market, with a 54.4% share in Q3. The company boosted its lead over Emulex by 1.9%, for a lead margin of 17.9%. In addition, according to the press release:

“On the 8Gb Fibre Channel adapter front, QLogic increased its revenue share by 3.6 percentage points compared to the previous quarter, increasing its revenue share lead to 56.6 percent for Q3. In the category of 8Gb Fibre Channel mezzanine cards, QLogic continued to dominate with 78 percent of revenue share for Q3 compared to the nearest competitor's 22 percent share. In the broader category of all mezzanine adapters (4Gb and 8Gb), QLogic increased revenue share by 1.6 percentage points to 72.4 percent and held a 44.8 percentage point lead for the quarter.”

On the FCoE CNA front, these two rivals had better ramp revenues, shipments and market share, because in the first half of next year NIC giants Broadcom and Intel will put both feet in the FCoE market and this will no longer be a Storage Vendors Only skirmish.

An Industry Brief released by IT Brand Pulse notes that CNA port volume shipments increased 133% in Q3, to a total of 9,800 ports, and revenue increased 148% to about $4 million.

In a blog post on FCoE CNAs, IT Brand Pulse CEO and senior analyst Frank Berry says that, “We could see a quantum increase in CNA volume very quickly if Broadcom and Intel position their 10Gb CNAs to displace some or all of the 10Gb NICs they have been shipping for years and that are now ramping at over 50% per quarter.”

For more of Frank’s opinions on the CNA market, see “Radar Picks Up CNA Growth In Q3.”

Disk drive/array market getting SASsier

May 18, 2009 – I just got the most recent disk drive shipment projections from IDC, and I was surprised – not only at the rapid ascendancy of SAS but also the rapid demise of Fibre Channel drives.

For example, if IDC’s projections hold up, SAS will account for a full 50% of all enterprise-level drive shipments this year. The rapid growth of SAS comes at the expense of Fibre Channel, which is expected to account for only 19% of drive shipments this year. Enterprise-class SATA drives are expected to make up the remaining 31%, according to John Rydning, IDC’s research director, hard disk drives (HDDs).

And by 2012, IDC estimates that Fibre Channel will have a mere 1% market share, compared to 25% for SATA and 74% for SAS.

“Fibre Channel will continue in small volume after this year, mainly for existing systems that will continue to sell in 2010 and for aftermarket support of current installations,” says Rydning.

He expects next-generation (6Gbps) SAS to further spur adoption of SAS drives (6Gbps arrays are expected near the end of this year), as well as “capacity optimized” drives with native SAS interfaces.

Personally, I don’t think Fibre Channel drives will bite the dust quite so rapidly, but I don’t have access to the raw shipment figures that Rydning does, and he’s been pretty accurate at predicting these things in the past.

I was just surprised at the SAS projections because I still think of SAS as the new kid on the block.

FCoE FUD

April 8, 2009 – At the only press conference at this week’s Storage Networking World confab, Brocade tossed its hat into the FCoE ring with the announcement of a switch and converged network adapters (CNAs). See “Brocade launches FCoE switch, adapters.”

That announcement seemingly officially kicked off the FCoE battles between Cisco and Brocade on the switch front, and Emulex, QLogic and Brocade on the CNA front. (As storage bigots, we’re ignoring the traditional NIC and switch vendors which may, or may not, eventually be contenders in the FCoE ring.)

Brocade’s CNA announcement came on the heels of similar announcements from Emulex and QLogic:

“QLogic delivers single-chip CNAs”
“Emulex CNAs support 10GbE, iSCSI, FCoE”

Upon each announcement, competitors offered their services in bad-mouthing their rivals. Since most of the claims and counterclaims are at this point are impossible to verify, we chose a Joe Friday approach to reporting the announcements – “Just the facts, ma’am.”

The FCoE battles may have begun in the OEM qualification arena (raising the question of how many CNAs or switches the big server/storage vendors will qualify/resell), but the real battles won’t begin until end-user adoption of FCoE begins. At yesterday’s press conference, Brocade CTO Dave Stevens predicted that we won’t see end-user adoption of FCoE in any volume until late 2010 (about the same time that 16Gbps Fibre Channel products are supposed to appear). And that might be optimistic.