Low-Cost Business Continuity Cluster Solution - Novell BUSINESS CONTINUITY CLUSTERING 1.2.1 - ADMINISTRATION Administration Manual

Figure 1-4 depicts a four-site business continuity cluster that uses storage-based data replication
between the sites. BCC uses eDirectory and Identity Manager to synchronize cluster information
between the two clusters.
Four-Site Business Continuity Cluster
Figure 1-4
Building A
Ethernet Switch
Server Server Server
1A 2A 3A
Fibre Channel
Switch
Fibre Channel
Disk Arrays
Cluster Site 1
Using additional software, all services, applications, and data can be rendered through the Internet,
allowing for loss of service at one site but still providing full access to the services and data by virtue
of the ubiquity of the Internet. Data and services continue to be available from the other mirrored
sites. Moving applications and services to the Internet frees corporations from the restrictions of
traditional LAN-based applications. Traditional LAN applications require a LAN infrastructure that
must be replicated at each site, and might require relocation of employees to allow the business to
continue. Internet-based applications allow employees to work from any place that offers an Internet
connection, including homes and hotels.

1.4.3 Low-Cost Business Continuity Cluster Solution

The low-cost business continuity cluster solution is similar to the previous two solutions, but
replaces Fibre Channel storage arrays with iSCSI storage arrays. Data block mirroring can be
accomplished either with iSCSI-based block replication, or host-based mirroring. In either case,
snapshot technology can allow for asynchronous replication over long distances. However, the low-
cost solution does not necessarily have the performance associated with higher-end Fibre Channel
storage arrays.
Four independent clusters in
geographically separate sites
WAN
eDirectory
IDM
Server Server
4A 1B
SAN
Disk blocks
Building C
Building B
Ethernet Switch
Server Server Server
2B 3B 4B
Fibre Channel
Switch
Fibre Channel
Disk Arrays
Cluster Sites 2, 3, and 4
Overview of Business Continuity Clustering
Building D
Server
4D
Server
4C
Channel
Channel
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