Crosswalk, the data protection management vendor, has introduced its grid storage product. The iGrid 5100 comes as two to eight nodes sitting between Fibre Channel-connected storage and gigabit Ethernet-connected servers. The servers see a single virtualised NAS resource. The nodes operate together to present the storage as a single global shared pool up to 4 exabytes in size. Accessing servers can use either NFS or the Windows CIFS protocol to access files.
They have parallel and scalable I/O to the stored files as each grid node can support 8 to 12 Gigabit Ethernet ports. The nodes, 3U rack units, have four 64-bit CPUs and 8 - 32 GB RAM. They connect to the storage via 8 Fibre Channel (FC) ports and the storage can be FC drives, FC-connected serial ATA (SATA) drives or FC-connected tape devices.
Data can be moved from one set of physical storage to another with accessing servers being unaware of the migration. New storage capacity can be added non-disruptively.
The grid nodes have high-availability features, such as automatic failover if one should fail. They co-operate to load-balance I/O traffic. Remote vaulting, backup and snapshots are supported. In future up to 255 grid nodes will be supported.
Crosswalk's launch makes the absence of equivalent high-end NAS products from EMC and NetApp more noticeable. It also contrasts strongly with grid storage concepts from HP, IBM and Sun. HP's smart cell-based grid concept, embodied in its RISS product, resembles EMC's Centera in its application. IBM has a file-based grid storage idea in Storage Tank which is being used in a Cern research project. Sun's grid storage is modelled exactly on a water or electricity grid and has storage capacity available over a network for a dollar a unit per time period. It just offers disk blocks for rent with no NAS or SAN organisation at all.