IBM Netfinity ServeRAID-4H Ultra160, User Reference

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Chapter 4. Introduction to IBM ServeRAID Cluster Solution
A cluster is a type of parallel or distributed system that consists of interconnected
computers that are used as a single, unified computing resource. In other words, a
group of computers linked together in such a way that they share and manage a set
of resources that can support a number of users at the same time.
This high-availability clustering solution is based on a two-server cluster, where both
servers can access the same storage devices, but only one server at a time
controls the storage devices shared by both servers. If one of the two running
server fails, the surviving server automatically assumes control of the shared
resources managed by the failed server while still controlling its own resources at
the same time. The failed server can then be repaired offline without the loss of
time or work efficiency because the shared data and applications earlier managed
by the failed server are still online to the clients.
When the failed server is operational again, it can be placed back into the cluster;
the resources are reallocated between the two servers and the cluster resumes
normal operations.
A controller is a device that coordinates and controls the operation of one or more
input and output devices, such as workstations, and synchronizes the operation of
such devices with the operation of a system as a whole.
IBM ServeRAID Cluster Solution, as discussed in this book, uses the IBM
ServeRAID-4H Ultra160 SCSI controller. IBM ServeRAID Cluster Solution also uses
IBM expansion enclosures, such as the following:
v
IBM Enterprise Expansion Enclosure (Model 3518)
v
IBM PC Server 3519 Rack Expansion Enclosure
v
IBM Netfinity EXP15 Rack Expansion Enclosure
v
IBM Netfinity EXP10 Rack Expansion Enclosure
v
IBM Netfinity EXP200 Rack Expansion Enclosure
v
IBM Netfinity EXP300 Rack Expansion Enclosure
You can install IBM ServeRAID Cluster Solution by using one of the following
software applications:
v
Microsoft Cluster Service, which is part of Windows NT Server Enterprise Edition
v
Microsoft Cluster Service using Windows 2000, which is part of Windows 2000
Advanced Server Edition or Windows 2000 Datacenter Server Edition
v
Vinca High Availability for Novell IntranetWare, which is part of the IBM Netfinity
Cluster Pack by Vinca
v
Novell High Availability Server 1.0
The following figures show an example of a simple high-availability clustering
solution. The first figure shows a high-level view of a cluster; the second figure
shows a more detailed view of a cluster.
© Copyright IBM Corp. 2000
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