Installation guide

EK–WNTMP–MH. D01 123995–002 1–1

Theory of Operation

This section provides an overview of StorageWorks Secure Path v2.2 for Windows NT.

1.1 An Overview of Secure Path for Windows NT

StorageWorks Secure Path is a high availability software product providing continuous

data access for Ultra SCSI RAID Array 7000 / Enterprise Storage Array 10000 and Fibre

Channel RAID Array 8000 / Enterprise Storage Array 12000 storage subsystems

configured on Windows NT 4.0 Intel or Alpha platforms. Redundant hardware, advanced

RAID technology and automated failover capability are used to enhance fault tolerance

and availability. Secure Path, in conjunction with your StorageWorks RAID Array

subsystem, effectively eliminates controllers, disk drives, interconnect hardware and host

bus adapters as single points of failure in the storage subsystem.

Secure Path v2.2 allows a StorageWorks dual-controller RAID subsystem to be cabled on

two independent SCSI busses or Fibre Channel loops, using two separate host bus

adapters in each server.

Secure Path monitors each path and automatically re-routes I/O to the functioning,

alternate path should an adapter, cable, hub or controller failure occur. Failure detection is

reliable and designed to prevent false or unnecessary failovers. Failovers are transparent

and non-disruptive to applications.

The Secure Path management utility provides continuous monitoring capability and

identifies failed paths and failed-over storage units. To facilitate static load balancing,

devices can be moved between paths using simple “drag-and-drop” operations.

Through the use of dual RAID controllers configured in an active/active multiple-bus

mode of operation, Secure Path can also exploit the potential for improved data

throughput and bandwidth performance.