Understanding Hard Disk Support in OS/2 and OS/2 LAN Manager

ID Number: Q67605

2.00

OS/2

Summary:

Included with OS/2 version 1.21 are two hard disk drive device drivers

named DISK01.SYS and DISK02.SYS. DISK01.SYS is designed to support ISA

and EISA Bus architectures, and DISK02.SYS is designed to support the

MCA bus.

OS/2 LAN Manager version 2.00 ships an extended version of these

drivers that provides the additional ability to do FT (fault

tolerance) (that is, disk mirroring and disk duplexing) and local

security.

To support their own kinds of hard disk devices, many OEM OS/2 vendors

ship their own version of these device drivers. Most OEMs, however, do

not include the code necessary to do OS/2 LAN Manager fault tolerance

and local security. As such, if your OEM or hard drive manufacturer

requires that you use a specific hard disk device driver, you probably

will not be able to run fault tolerance or local security on your OS/2

LAN Manager machine.

If your system matches the scenario above, DO NOT choose the option

to install the extended DISK01.SYS or DISK02.SYS drivers during the

OS/2 LAN Manager Setup.

More Information:

In the PC environment, there are three major bus architectures (ISA,

EISA, and MCA) and six major hard disk drive types (RLL, SCSI, MFM,

IDE, and ESDI) that run on these architectures. For a bus to be able

to understand a particular hard disk drive type, your machine must

have a hard disk drive controller card that can use both the bus and

the drive type.

For example, a SCSI hard disk drive can run on an ISA, EISA, or MCA

bus as long as the hard disk drive controller card can communicate

with both the bus and the hard disk drive.