Dell AX4-5 - Manual (Page 46)

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Understanding Your Failover Cluster
An active/active configuration contains virtual servers running separate
applications or services on each node. When an application is running on
node 1, the remaining node(s) do not have to wait for node 1 to fail. Those
node(s) can run their own cluster-aware applications (or another instance of
the same application) while providing failover for the resources on node 1. For
example, multiway failover is an active/active failover solution because
running applications from a failed node can migrate to multiple active nodes
in the cluster. However, you must ensure that adequate resources are available
on each node to handle the increased load if one node fails.
In an active/passive configuration, one or more active cluster nodes are
processing requests for a clustered application while the passive cluster nodes
only wait for the active node(s) to fail.
Failover Policies
When implementing a failover policy, configure failback if the cluster node
lacks the resources (such as memory or processing power) to support cluster
node failures.
Windows Server 2008 Cluster Configurations
Cluster configurations running Windows Server 2008 provide the following
failover policies:
• N (number of active nodes)+ I (number of inactive nodes) failover
• Failover pair
• Multiway failover
• Failover ring
Table 4-4 provides an overview of the failover policies implemented with
Windows Server 2008. For more information, see the sections that follow
this table.