Looking for a surefire way to simplify SAN administration and make integration a snap? Look no further than virtualization, the secret sauce in the Fujitsu Software Technology (Fujitsu Softek) and IBM solutions.
IBM calls its virtualization server Volume Manager. Fujitsu Softek prefers the term "provisioning" and calls its product Storage Provisioner. The concept is the same: installing a dedicated server that acts as a FC proxy between the storage network's servers and disk arrays. By taking control of all storage and by presenting the storage to the servers in a controlled fashion, a virtualization server truly is the integration solution. But that's at a potential cost of adding an increased layer of software management for every disk read and write operation.
Fujitsu Softek and IBM have implemented their virtualization solutions differently. IBM offers hardware appliances that must be deployed in pairs; Fujitsu Softek sells a pure software solution that can run on generic x86 servers. Again, the concept is the same. The virtualization server is connected to the FC SAN using two sets of HBAs. One set of adapters looks to the SAN switch, like a server, designed to consume storage; the other set appears to be a disk array ready to supply storage.
In operation, the virtualization server takes control of some or all of the available disk resources on the storage network and turns the SAN into a single large pool of storage. It then allocates that storage to other servers connected on the storage network, providing a single point of control. This is greatly simplified administration: When a disk array's volumes have been assigned to the virtualization server, the disk array need not be maintained again. Similarly, administrators can use the virtualization server as a one-stop-shopping resource for allocating disk space to servers. No more scavenging for unused megabytes, no more shuffling volumes from one array to another. The virtualization server takes care of and masks all those details.
IBM and Fujitsu Softek provide two ways of assigning storage to the virtualization server: The solutions can take over unused disk space and move existing array volumes that have been assigned to servers. IBM has the advantage in sheer ease of use. Its Volume Manager systems are dead simple to install and configure. Fujitsu Softek, on the other hand, excels at scalability and high availability, as its Storage Provisioner can be installed on larger, higher capacity servers, and deployed in N+1 configurations with multiple hot spares. IBM's system is Big Blue-centric and designed to act primarily as a front-end processor to IBM's own storage arrays. Fujitsu Softek supports just about every storage device on the planet.