Administrator Guide

132 | Deploying W-ClearPass Clusters Dell Networking W-ClearPass Deployment Guide
The cluster feature allows for shared configuration and databases. However, it does not provide a virtual IP
address for the cluster, so failover/redundancy for captive portal for Guest relies on Domain Name System
(DNS) lookup or load balancing.
RADIUS clients must define a primary and backup RADIUS server.
Authentication Requests in a Cluster
The typical use case for Policy Manager is to process authentication requests using the policy framework. The
policy framework is a selection of services that work to process authentication requests, but the policy
framework also determines authentication, authorization, posture, enforcement, role, etc. of the
endpoint/end-user.
In the context of cluster operations, authentication typically involves a read-only operation from the
configuration database. A cluster node receives an authentication request, determines the appropriate policies
to apply, and responds appropriately. This does not require a configuration change, and can therefore be
scaled across the entire cluster.
Authentication is performed from the node itself to the configured identity store, whether locally (as synchronized by
the Publisher, for example, a Guest account) or externally, such as with Microsoft Active Directory.
Logs relevant to each authentication request are recorded separately on each node, using that node’s log
database. Centralized reporting is handled by generating a Netevent from the node, which is sent to all Insight
nodes and recorded in the Insight database (for related information, see Deploying W-ClearPass Insight in a
Cluster on page 152).
W-ClearPass Databases
Each W-ClearPass server makes use of the following databases:
l Configuration database. Contains most of the editable entries that can be seen in the W-ClearPass user
interface. This includes, but is not limited to:
n Administrative user accounts
n Local user accounts
n Service definitions
n Role definitions
n Enforcement policies and profiles
n Network access devices
n Guest accounts
n Onboard certificates
n Most of the configuration shown within Guest and Onboard
l Log database. Contains activity logs generated by typical usage of the system. This includes information
shown in Access Tracker and the Event Viewer.
l Insight database. Records historical information generated by the Netevents framework. This database is
used to generate reports (for related information, see Deploying W-ClearPass Insight in a Cluster on page
152).
Publisher/Subscriber Model
W-ClearPass uses a Publisher/Subscriber model to provide multiple-box clustering. Another term for this model
is hub and spoke, where the hub corresponds to the Publisher, and the spokes correspond to the Subscribers.