Asus PCI-SIU2, Руководство пользователя

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ASUS PCI-SIU2 User’s Manual 23
If both SCSI and non-SCSI (for example, IDE) disk drives are installed, then
the non-SCSI disk drive is typically the boot drive. If your computer supports
BBS (BIOS Boot Specification), both SCSI and non-SCSI disk drives can
coexist and you can specify which drive to boot from. Refer to your computer
documentation for more information.
Low-level Format
A low-level format will erase any data that is stored on the target disk. Before
attempting to perform a low-level format be sure the data on the target disk
has been backed up. A low-level format can be achieved via the SmartSCSI
Setup Utility for PCI-SIU2.
The low level format sets the media to a state which is easily recognized by
the host adapter on the SCSI bus. Once this format is completed, you will
need to partition the drive. Refer to your operating system documentation for
further information on partitioning drives.
Multiple Initiators & Clustering
A multiple initiator environment is one in which the SCSI bus has two or more
host adapters. To work in a cluster, the host adapters must perform properly in
such an environment by not resetting the bus without an explicit host com-
mand, for example. ASUS’s host adapters are built for multi-initiator opera-
tion and adhere strictly to the SCSI standard.
FIGURE 11 illustrates the principal components in a cluster’s I/O system. It
shows a simple cluster with two servers sharing access to online storage (the
basic model for Microsoft’s MSCS clusters). Both servers contain a host
adapter that provides access to the shared external I/O bus. Servers can share
disks or arrays attached to this shared I/O bus. The operating system controls
contention for disk access by using either a component called a distributed
lock manager (DLM) to resolve access conflicts or a shared-nothing model
that partitions disks and arrays, giving each server control over a subset of the
storage under normal circumstances. MSCS uses the shared-nothing approach.
Under some circumstances multiple initiators can be used on a single SCSI
bus. The bus is configured to have more than one host adapter inserted into at
least two distinctly different computer systems sharing peripheral devices. In
these circumstances, it is possible to have one of the two computer systems
turned off. Under these conditions,
3. Hardware Installation