Communicator e3000 MPE/iX Release 7.0 Express 1 (Software Release C.70.01) (30216-90328)

110 Chapter5

Technical Articles

Announcing High Availability FailOver for the SureStore E Disk Array XP256

Announcing High Availability FailOver for the

SureStore E Disk Array XP256

Kendall Sutton

Commercial Systems Division

General Information

High Availability FailOver (HAFO), using the XP256 high availability data storage array,

is now available for MPE/iX systems as part of the Fundamental Operating System (FOS).

HAFO is supported only with the XP256 with a direct connect SCSI interface..

Once the HAFO utilities are installed, the user conﬁgures the LDEV, a primary data path,

and an alternate data path. In a normal state, data is routed through the primary path,

while HAFO utilities continually monitor SCSI reply messages for failed SCSI data path

components. Any of these three occurrences will generate a failover:

• hung I/O

• failed disk controller

• failed I/O host device adapter card

In the event of a failover, the HAFO utilities create the conﬁgured alternate data path and

reroute I/O to it. No application or higher level MPE/iX Operation System (above I/O

subsystem--for example, ﬁle subsystem, database management, or memory management

subsystem) will experience an abnormal event. All I/Os complete as normal using the

alternate data path and alternate array controller.

Who Should Use HAFO

HAFO is for XP256 customers wanting protection against failure for the following

components of the I/O subsystem:

• I/O host adapter card

• SCSI bus cabling

• Disk controller

Required Hardware and Software

Required Hardware

• HP e3000

• SureStore E Disk Array XP256

Required Software:

• MPE/iX Version 7.0 or later

• Patches KXD2, KXD3, KXD4, LX95