Novell BUSINESS CONTINUITY CLUSTERING 1.0 - ADMINISTRATION Manual page 16

synchronous replication over short distances. The illustration below depicts a four-site business
continuity cluster.
Figure 1-4
Server
1A
Fibre Channel
Using Novell's Portal Services, iChain®, and ZENworks® products, 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.
Low Cost Business Continuity Cluster Solution
The low cost business continuity cluster solution is similar to the previous two solutions, but
replaces Fibre Channel arrays with iSCSI arrays. Data block mirroring can be accomplished using
iSCSI-based block replication. In this case, snapshot technology can allow for asynchronous
replication over long distances. However, the lower cost solution does not necessarily have the
performance associated with higher-end Fibre Channel storage arrays.
16 Novell Business Continuity Cluster Services 1.0 Administration Guide
Multiple Site Business Continuity Cluster
Four independent clusters in
geographically separate sites
Building A
Ethernet Switch
Server Server Server
2A 3A 4A
Switch
Fibre Channel
Disk Arrays
Cluster Site 1
Building B
Ethernet Switch
WAN
eDirectory
Server
DirXML
Server Server
1B 2B
SAN
Disk blocks
Fibre Channel
Disk Arrays
Cluster Sites 2, 3, and 4
Building D
Building C Ethernet Switch
Ethernet Switch
Server Server Server
1D 2D
Server Server Server
1C 2C 3C 4C
Server Server
3B 4B
Fibre Channel
Switch
Fibre Channel
Switch
Fibre Channel
Disk Arrays
Fibre Channel
Disk Arrays
Server
3D 4D
Fibre Channel
Switch