WebSphere Application Server V7.0: Concepts ... - IBM Redbooks

Disadvantages
The disadvantages of this topology are as follows:
► Complex administration
Due to the heterogeneous environment, the administration is complex and
requires administrator knowledge for all platforms.
► Increased administration and operational costs
This combined topology has the disadvantages of costs in hardware,
configuration, and administration. Consider these costs in relation to gains in
performance, throughput, and reliability.
For information about planning and system considerations required to build a
heterogeneous cell, see the IBM White Paper WebSphere for z/OS --
Heterogeneous Cells, available at the following Web page:
http://www.ibm.com/support/techdocs/atsmastr.nsf/WebIndex/WP100644
5.3.7 Multi-cell topology
The topologies introduced in 5.3.5, “Topology with redundancy of multiple
components” on page 160, and in 5.3.6, “Heterogeneous cell” on page 166
provide a high level of availability and redundancy of all sorts of WebSphere
components. Nevertheless, application software problems or malfunctioning of
cell level components such as high availability manager, though rare, are
potential threats to the availability of your service.
High availability and disaster recovery are two terms that need to be addressed
differently. A possible approach would be a two cell architecture as outlined in
Figure 5-10 on page 169
168 WebSphere Application Server V7.0: Concepts, Planning, and Design