EMC and IBM separately have unveiled midrange network-attached storage products for users who want to combine and manage NAS and storage-area network technology.
NAS appliances let users write file-oriented data to file servers connected to the IP network. NAS gateways give users access to block-level data stored on SANs via the IP network and let users access and manage file- and block-level SAN data from one source.
EMC this week is releasing three midrange NAS appliances - the NS500, NS500G and NS704G - which fit between the company's low-end Microsoft Storage Server 2003-based NetWin NAS appliances and its high-end Celerra. The NS500 is a NAS appliance that supplies easily accessible storage to IP network users; the NS500G and NS704G are gateway servers that attach to Fibre Channel or Advanced Technology Attachment (ATA) storage and let it be managed and accessed along with NAS storage.
IBM last week introduced the IBM TotalStorage NAS Gateway 500, which is based on one Power4+ processor and complements its higher-performance two- to four-processor product.
Laurie Beam, director of technology for law firm Smith Anderson chose a NAS gateway to link her existing file servers to the firm's SAN, which contains the firms' business-critical documents.
"By using a gateway to link our file server data with our SAN data, we are able to manage it from a single virtualized pool," Beam says.
She uses the NS600G, EMC's previous NAS gateway, to connect her EMC Clariion SAN to the file servers on her network.
The EMC NS500 consists of a dual 1.6-GHz controller with four 10/100/1000 Gigabit Ethernet connections and as much as 4T bytes of useable Fibre Channel storage and 12T bytes of ATA drive capacity per storage controller. The NS500 uses one or two 1.6-GHz controllers.
The NS500G is a dual-processor gateway that also can attach to as much as 16T bytes of storage per controller. The NS700G is a gateway NAS product that has four controllers and as much as 8T bytes of useable Fibre Channel and 8T bytes of ATA capacity per controller.
EMC also has enhanced the management capabilities of its high-end Celerra NAS array. Celerra's management software now includes the ability to collect statistics such as CPU usage, number of Common Internet File System connections and files and file system and device throughput. Furthermore, users can export these statistics for use in other programs.
EMC also has improved the integration of Microsoft's Volume Shadow-copy Services with Celerra, which lets users recover deleted files without the assistance of an IT manager. Each EMC NS appliance is now iSCSI-capable, letting customers without SANs migrate to block-level Fibre Channel storage.
Storage growth capacity
With the new IBM TotalStorage NAS Gateway 500, customers can scale from one processor to two, four or eight processors as their needs for storage accessibility and performance change.
The new product includes support for three modes of mirroring data over IP networks - asynchronous, synchronous and Mirror Write Consistency (MWC). MWC writes data to the local disk at the same time it is sent to the remote site. IBM says MWC is faster than synchronous and more reliable than asynchronous mirroring.
The new NAS Gateway 500 also includes support for Windows 2003 and EtherChannel, which allows load balancing among Ethernet connections for increased performance. The gateway is a rack-mountable 4U-high appliance that uses an IBM pSeries server as its controller. A cluster interconnect kit is available, which links two NAS Gateway 500s together to provide fault-tolerance and availability.
EMC's and IBM's gateways are not alone in this market. The EMC NS500 compares to the Network Appliance FAS270 and the IBM TotalStorage NAS Gateway. The EMC NS704G compares to the Network Appliance 960 C cluster and IBM's more-powerful two-eight TotalStorage NAS Gateway 500. Each of these boxes is more powerful than the Microsoft Windows Storage Server boxes from Dell, HP and IBM.
The IBM TotalStorage NAS Gateway 500 is expected to be available next month starting at US$60,000. A dual-controller EMC NS500 with 1T byte of capacity starts at US$81,000; the NS704G starts at US$165,000. The NS500G starts at US$52,300.