Multiprotocol storage, also known as "unified" or "federated storage," provides block-based access using SAS, Fibre Channel and iSCSI, along with NAS or file-based access using NFS and CIFS for Windows file sharing in an integrated solutions package. Smaller environments with general storage needs, including remote or branch offices, small-midsized business (SMBs), and small office/home office (SOHO) environments can benefit from using multiprotocol storage.
The advantages of multiprotocol storage products include the ability to adapt to various application requirements. For example, lower end or entry-level SMB and even SOHO-based multiprotocol storage has a value proposition similar to that of multifunction printers, copiers, scanners and fax machines. That value proposition is being able to do more as a single device to remove cost and complexity without compromising on functionality.
Multiprotocol storage products allow you to easily do the following things:
- Acquire and install it without need for a specialist
- It can be used by professionals with varied skills
- It can be reprovisioned for different applications requirements
- It can be expanded and upgraded to boost future capacity needs
NAS solutions have evolved to support both NFS and CIFS along with other TCP-based protocols, including HTTP and FTP concurrently. NAS or file sharing-based storage continues to gain popularity because of its ease of use and built-in data management capabilities. However, some applications, including Microsoft Exchange or databases, either require block-based storage using SAS, iSCSI or Fibre Channel or have manufacture configuration guidelines for block-based storage.
For smaller or departmental environments, all or most storage needs may be supported by a multiprotocol storage solution, while others may have a multiprotocol solution and a traditional block-based or NAS-based storage server.
More recently, NAS solutions have further evolved to support iSCSI block-based storage over an Ethernet-based network interface traditionally used for NFS or CIFS. Some NAS solutions have further evolved to support additional physical interfaces, including Fibre Channel with FCP or TCP over InfiniBand. A differentiator between multiprotocol storage systems can be how integrated the multifunction capability is. For example, the
multifunction capability can be created by packaging different products in a common cabinet or enclosure. Separate management tools may be needed unless a custom GUI or management tool is supplied. An example of a cabinet or enclosure-based solution would be an existing Fibre Channel or SAS storage array with a NAS gateway or NAS head attached to the storage system and either native iSCSI on the storage array itself, or via the NAS gateway.
Microsoft Windows Storage Server (WSS)-based NAS appliances are popular as a means of enabling NAS capability for existing SAS, Fibre Channel or iSCSI storage systems.
For vendors, the advantage of creating a multiprotocol system via packaging and special management toolsets is the ability to use existing technologies. For example, EMC Corp.'s multiprotocol NAS solutions use Clariion AX- and CX-based storage arrays for block-based access and provide NAS functionality via their Celera devices using a common storage pool to meet various price points.
Other approaches gaining popularity are those that are designed and built from the ground up as multiprotocol storage systems instead of retrofitting existing products. The advantage of multiprotocol storage systems that are native by design is tighter integration of feature functionality and less dependency on integration via custom add-on GUIs and management tool sets.
A common example of a multiprotocol storage solution integrated by design includes those based on Microsoft Windows Storage servers that support NFS, CIFS and iSCSI access from servers using various disk storage options.
Examples of multiprotocol storage with built-in or native capabilities include the Microsoft WSS-powered Dell PowerVault NX1950 and Hewlett-Packard (HP) Co. AiO, as well as the NetApp Inc. StoreVault storage servers and BlueArc Corp. Titan.
Using gateways, routers or protocol conversion appliances, other non-multiprotocol storage systems can be transformed for mixed mode use. Multiprotocol SMB storage, particularly for entry level, can be very affordable with solutions starting at less than $10,000 with good scalability compared to more scalable SMB solutions that may require a small business administration loan to acquire.
It should come as no surprise that HP is involved with multiprotocol storage because of its success with multifunction printers that combine the capabilities of a printer, copier, scanner and fax machine in a single, easy to use and affordable solution.
Longtime NAS vendor NetApp has also entered the multiprotocol storage game targeted at SMBs with its StoreVault product. NetApp also adapted its midmarket and enterprise NAS solutions to support block-based storage access using iSCSI and Fibre Channel.
Caveats of unified or multifunctioned storage include:
- Limited scaling capabilities of smaller all-inclusive storage appliances
- Performance may be compromised in favor of ease or use or functionality
- Some functionality may be an either/or situation, meaning NFS or CIFS, or iSCSI or Fibre Channel, or block or file, but not both at the same time
- You must determine which operating systems and applications are supported by the solution
Look for product that have the ability to scale to meet your current and future storage capacity, performance and availability needs or that can coexist under common management with additional storage systems.
Also, consider which management and storage software tools are included. For example, is local and remote mirroring or data replication included along with snapshots, data migration and general purpose configuration and management tools? Check to see if solutions have any hidden fees for activating and using the different protocols and functional capabilities.
About this author: Greg Schulz is founder and senior analyst with the IT infrastructure analyst and consulting firm StorageIO.
This was first published in August 2008