Marathon Technology Corp’s Endurance 4000 fault tolerant system for Windows NT is now shipping in Europe through London-based Just Associates. The system provides fault tolerance for clustered NT server systems, which despite recent claims, can only really claim to offer high availability. The Endurance 4000 system runs a four computer configuration – two computers are a synchronized mirrored pair of Computing Elements that can be any matched, uni-processor Pentium Pro desktop or server PC. The other two computers are run as Pentium Pro-class input/output processors. When the failed electronics, disk, network interface or power supply is replaced, Computing Elements are synchronized by copying memory while the I/O processors automatically copy up- to-the-moment data to the new disk. The Marathon Interface Card links the I/O and CE to the split site data link that enables the synchronization of the operation – ensuring that no data is lost when either CE or I/O processor goes down and that users are unaware of the failure. Systems managers can monitor the system and will be alerted to the problem, while there is also a port to an external alarm system. Currently, Endurance offers 99.99% availability, which equates to roughly 50 minutes down time per year, although Marathon is aiming for 99.997%, equivalent to just 7 minutes per year. Endurance is available now from Just Associates for 25,000 pounds, and for an additional 3,000 pounds for a fiber-optic wiring edition, although four Microsoft NT licenses are also currently required..
