|
NetApp's SpinServer is a clustered file system for NFS that currently doesn't support CIFS. SpinServer exports a single namespace across all storage nodes, but files aren't striped across nodes. There aren't special nodes for meta data and storage; instead, all nodes support both meta data and storage services.
Ibrix, Red Hat Global File System (GFS) and others offer software-only clustered or parallel file systems. Most of these products require special client software to be installed and the file system must operate on all clients accessing file data.
Red Hat GFS can be configured on a Linux box to handle NFS and CIFS as well as GFS clients. GFS supports two or more cluster nodes. CIFS support is via Samba services available under Linux. Red Hat GFS currently supports NFS V2 through V4 and can be connected to any back-end storage accessible to Red Hat Linux.
Parallel file-system products: HP StorageWorks Scalable File Share (SFS) is an outgrowth of the Lustre project and has special meta data and storage processing nodes. To access file data in parallel, special client software is needed, which is available for most forms of Linux and has recently become available for Mac OS X. However, SFS doesn't support CIFS and has limited scalability for clients using NFS. To gain maximum benefit from this system, you need to run the Lustre file system.
The Panasas ActiveScale File System supports native parallel file access using its DirectFlow protocol, and also supports standard NFS and CIFS access. The product consists of separate DirectorBlades and StorageBlades that plug into a shelf. DirectorBlades act as meta data servers controlling access and mapping file names to StorageBlade locations, and as protocol servers for mapping NFS and CIFS protocols to the internal DirectFlow protocol. Performance scales with capacity, and therefore bandwidth will increase as additional shelves are deployed. All shelves are virtualized to provide a single, global file namespace for client application access and system management. Panasas storage systems can be integrated into an existing infrastructure and co-exist with non-Panasas NAS storage or be deployed as a replacement for those systems.
NAS aggregators: A new class of storage products provides an aggregated view of multiple, heterogeneous NAS boxes. These products provide a single GNS over all file systems for a set of NAS boxes. NAS aggregators, or network file managers, are great for companies consolidating NAS data from a number of different vendor NAS products or retaining multivendor NAS configurations. The primary advantage of these products is their support for a single namespace across all NAS boxes under their control. Their main disadvantage is that they add another box with additional overhead to the storage environment that needs to be installed, configured and maintained.
Acopia Networks Inc.'s Adaptive Resource Switch (ARX) is an in-band aggregator of NAS services. It supports remote site replication across heterogeneous NAS boxes and can provide quick access to remote data if primary site data services go down. Acopia offers a high-availability option with two boxes configured as an active/active or active/passive pair. There are three ARX models that provide different levels of performance. As with any in-band appliance, bandwidth requirements are an important consideration for any deployment.
|
