* NEC joins others in the Windows server failover market
The server failover market heated up last week as NEC introduced a new version of its ExpressCluster X WAN Edition for Windows.
NEC joins a number of vendors in this market, including Neverfail, Doubletake Software, CA (through its acquisition of XOSoft) and Microsoft.
NEC’s failover product is designed for Microsoft Windows environments and has specific support for Microsoft Exchange. NEC ExpressCluster X WAN provides the ability to choose or change between synchronous and asynchronous disk mirroring modes. It also features a Web-based graphical user interface and remote management capabilities.
Based on either polling or notification of the lack of a heartbeat signal, the ExpressCluster X WAN Edition can automatically execute recovery procedures if a system fails. Applications and data can be recovered within minutes instead of hours or days.
The ExpressCluster X WAN Edition supports Intel x86 servers and NEC’s own fault-tolerant servers that run Microsoft Exchange Standard or Exchange Enterprise editions on industry standard Windows server operating systems.
ExpressCluster X WAN Edition also joins two other NEC products – ExpressCluster SAN (storage-area network) and ExpressCluster LAN. The product is configured in a one-server-to-one-server relationship.
In synchronous mirroring using ExpressCluster, the primary server receives a “write” request from the application. The primary writes data to disk and forwards it to the standby server. The standby writes data to its own disk and sends the result to the primary server. The primary server receives the result from the standby server and returns result and control back to application.
In asynchronous mirroring using ExpressCluster, the primary receives a “write” request from the application. The primary writes data to its disk and forwards it to the standby. The primary receives the result from its disk and returns the result and control back to the application, while the standby continues to write data to its disk. The standby sends the result to the primary server.
ExpressCluster X WAN Edition is available for $16,000 for a two-server configuration. Versions for Linux and other operating systems are expected to be available next year.
