Mirroring - Compaq PORTABLE 386 Maintenance And Service Manual

To use MS-DOS and the device driver with two fixed disk drives and one fixed
disk drive expansion unit:
o A maximum of two controllers can be plugged into the system bus.
o Each controller can support only two fixed disk drives.
Example: With the use of two fixed disk drive expansion units, a total of
1.2 gigabytes of fixed disk drive storage is available, divided into four
300 megabyte volumes.
NOTE: For maximum storage, the system is connected in the same way as for
duplexing or mirroring.
mirroring or duplexing is that the Novell NetWare software does not need to be
used when the system is configured for maximum storage.

Mirroring

IMPORTANT: Novell NetWare software must be used when setting up the system
for proper operation of the mirroring function.
A possible mirroring configuration currently supported by Compaq Computer
Corporation uses one fixed disk drive expansion unit with two 300 megabyte
fixed disk drives.
into the system bus and connected with a cable to an external interface
adapter mounted in the fixed disk drive expansion unit complete this
implementation (Figure 10-2).
duplicated in the other.
This configuration is shown in Figure 10-1.
The only difference between maximum storage and
A single external fixed disk drive controller, plugged
Data written to one fixed disk drive is exactly