Installation guide

Using LVS with Red Hat Cluster
You can use LVS routers with a Red Hat Cluster to deploy a high-availability e-commerce site that
provides load balancing, data integrity, and application availability.
The configuration in Figure A.1, “LVS with a Red Hat Cluster” represents an e-commerce site used for
online merchandise ordering through a URL. Client requests to the URL pass through the firewall to the
active LVS load-balancing router, which then forwards the requests to one of the Web servers. The Red
Hat Cluster nodes serve dynamic data to the Web servers, which forward the data to the requesting
client.
Figure A.1. LVS with a Red Hat Cluster
Serving dynamic Web content with LVS requires a three-tier configuration (as shown in Figure A.1, “LVS
with a Red Hat Cluster”). This combination of LVS and Red Hat Cluster allows for the configuration of a
high-integrity, no-single-point-of-failure e-commerce site. The Red Hat Cluster can run a high-availability
instance of a database or a set of databases that are network-accessible to the Web servers.
A three-tier configuration is required to provide dynamic content. While a two-tier LVS configuration is
suitable if the Web servers serve only static Web content (consisting of small amounts of infrequently
changing data), a two-tier configuration is not suitable if the Web servers serve dynamic content.
Dynamic content could include product inventory, purchase orders, or customer databases, which must
be consistent on all the Web servers to ensure that customers have access to up-to-date and accurate
information.
Using LVS with Red Hat Cluster
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