Evolutionary Step for Storage

 
 
By Henry Baltazar  |  Posted 2003-09-15
 
 
 

SAN technology is about to take an intelligent step forward. Until now, storage management applications have run smoothly on hosts or enterprise-class storage devices. This arrangement has been workable because most storage area networks have been relatively small.

However, SANs are getting bigger and more complex, and that trend will certainly continue as IT departments implement storage consolidation to simplify management, and vendors exploit the advances being made in storage networking technology.

Factor in the recently released IP storage technologies, which will open the world of SANs to lower-end servers and workstations, and its easy to see why the need to simplify management of storage resources is greater than ever. (For eWEEK Labs review of Cisco Systems Inc.s MDS 9216 Multilayer Fabric Switch, which blends characteristics of IP and Fibre Channel SANs, click here).

IT managers, understandably, are no longer willing to trust their storage to standard server-class hardware that has limited performance and scalability potential.

Although current management schemes work well for enterprise-class storage devices, these devices are extremely vendor-centric. They provide superior manageability in the short term, but customers can easily get locked into a vendors products for several years as storage management standards continue to develop.

Storage virtualization stands to be the killer app for intelligent SAN switches because of their placement in the center of the network and their high-performance characteristics. Its no surprise, then, that switch vendors including Brocade Communications Systems Inc., Cisco, Maxxan Systems Inc. and McData Corp., among others, are working hard to get storage virtualization software running on their switch platforms.

In any SAN, switches are the central points to which all other storage devices are connected, so adding intelligence to these switches makes sense. Based on what eWEEK Labs has seen so far, the migration to this new class of switches should be almost seamless: In all likelihood, IT managers will be able to add intelligent switches that run side by side with older switches with a minimum of trouble.

Centrally located intelligent SAN switches can quickly determine the capacity, bandwidth needs and online/offline status of hosts. Intelligent SAN switches can connect to these hosts as well as to the storage devices to which they connect through the SAN.

Leveraging this position in the network topology, intelligent SAN switches can provide hosts with access to storage resources when RAID units are plugged into the switches.

Their central location in a SAN means that intelligent SAN switches can also be valuable for data protection applications such as mirroring and asynchronous replication. Intelligent switches can redirect storage data from a primary storage unit to a replication target without disrupting a host server.

Furthermore, because SAN security is becoming a hot issue, intelligent SAN switches are in a good position to enhance security by monitoring the access of authorized hosts to the storage units while preventing rogue hosts from seeing storage resources.

These switches are designed to be scalable and are capable of channeling large amounts of data, so they are far more attractive for managing storage traffic than are storage management servers, which are potential bottlenecks and points of failure. In fact, one major obstacle to the adoption of storage virtualization technologies during the last few years has been the reluctance of many IT managers to have all their storage bandwidth funneling through standard servers running virtualization software.

Although virtualization seems to be the most logical application for intelligent SAN switches, our visits with SAN switch vendors showed it is clear that these switches will be used in a wide range of applications.

In our review of the Maxxan SA100f appliance, we got a first real look at the potential of intelligent SAN switches.

With only one vendor selling product, its clear that intelligent SAN switches are part of a technology segment in its infancy. But based on hardware and software vendors feverish development pace and the fact that SAN implementations can take several months to plan, test and implement, it is crucial to watch this space now.

Senior Analyst Henry Baltazar can be reached at henry_ baltazar@ziffdavis.com.

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