Introduction

I am not the typical enterprise storage user. In fact, I’m not an enterprise storage user at all — I’m a consultant focused for over a decade on assisting enterprises with their storage architecture and strategy, working with businesses of all sizes, and have never worked for a vendor of storage hardware or software. I’ve also written for Storage magazine, InfoStor, and others for many years, and speak at enterprise storage conferences.

This is both a blessing and a curse — I have seen far more enterprise storage environments in much more detail than most people, but I am unable to truly empathize with my corporate storage compatriots since it’s not really my gear and data that I’m working with.

However, I feel that it would not be inappropriate for me to comment on this challenge. Specifically, I am would like to comment on the future of the SAN market.

How do you see the current SAN market, and where do you think it’s going?

Although the commoditizing storage market would seem ripe for stagnation, the opposite is happening. In fact, the SAN market has continued to diversify, with iSCSI recently expanding the options for storage connectivity to a new market and FC seeing rapid uptake in the virtual server arena. Fibre Channel over Ethernet (FCoE), whether or not part of the datacenter Ethernet push, is joining virtualized I/O technology based on InfiniBand as the next wave in connectivity. Simply put, the SAN market is not standing still.

Focus on the new world of SAN connectivity can take away from the basics, however. Traditional switched Fibre Channel remains the healthy market leader, and the recent upgrade to 8 Gb speed has attracted customer attention. Although they are unlikely to run out and perform a mass upgrade, I see 8 Gb FC as as much of an inevitability as 4 and 2 Gb before it. The switch will be made, and customers will upgrade organically.

One of the big beneficiaries of 8 Gb FC will be those with virtual servers. This new hardware is coming just as N_Port ID virtualization (NPIV) is maturing, and the combination of this with a doubling of bandwidth will make this tech extremely attractive to virtual server shops.

Even those who do not adopt 8 Gb FC connectivity in their SAN will benefit from the upshift in throughput, though, as native 8 Gb disks appear and enterprise arrays are redesigned to accept them, just as devices like the DMX-4 from EMC benefited from 4 Gb FC back ends.

As far as iSCSI goes, I think that those of us who saw the promise of this technology can finally declare victory. Every storage device that matters offers iSCSI as a connectivity option, and most buyers are considering adopting it. It is being weighed fairly against FC, and the promise of reduced heterogeneity and cost are proving attractive to many. In fact, it is wrong to continually compare it against FC, since many iSCSI buyers would never adopt an FC SAN due to concerns about cost or learning curve. Indeed, much of the uptake in iSCSI comes from areas where SAN was never adopted, and iSCSI’s growth can be partly attributed to these happy customers spreading the technology wider than originally intended.

One of the prime benefits we have seen of iSCSI adoption are the technologies and techniques that have come along with it. Clustering of smaller storage systems has become a common option for scalability, and has proven itself against old modular “head/shelf” arrays. Although the rate of adoption for security technologies like CHAP and IPsec in iSCSI remains low, they are far more common than their FC relatives. And Microsoft’s move to simplify iSCSI drivers, especially multipathing and snapshotting, has been much more successful than their proprietary equivalents.

Let us not forget humble old NAS, either. File server consolidation to NAS filers continues to be a healthy (but less flashy) market, and NAS virtualization is on the rise as these devices proliferate. And some in the server virtualization community are beginning to consider NFS for their (especially VMware) servers. NAS definitely still has life and legs and will benefit from the shift to 10 Gb Ethernet just like iSCSI and FCoE.

As for the future, it is clear that most storage vendors are lining up behind FCoE. Although true I/O virtualization, as envisioned by datacenter Ethernet and InfiniBand, may not gain traction outside the largest data centers, FCoE seems to be the inevitable next generation for massive enterprise storage. Just about every vendor is committed to it, and the customers I have spoken to accept it as the future. Although 8 Gb FC might delay FCoE in some cases, it will almost certainly be the predominant SAN connectivity mechanism for large block storage devices within five years.