User Guide

CHAPTER
39-1
AsyncOS 9.1.2 for Cisco Email Security Appliances User Guide
39
Centralized Management Using Clusters
• Overview of Centralized Management Using Clusters, page 39-1
• Cluster Requirements, page 39-2
• Cluster Organization, page 39-2
• Creating and Joining a Cluster, page 39-4
• Managing Clusters, page 39-10
• Administering a Cluster from the GUI, page 39-15
• Cluster Communication, page 39-18
• Loading a Configuration in Clustered Appliances, page 39-22
• Best Practices and Frequently Asked Questions, page 39-24
Overview of Centralized Management Using Clusters
The Cisco centralized management feature allows you to manage and configure multiple appliances at
the same time, reducing administration time and ensuring a consistent configuration across your
network. You do not need to purchase additional hardware for managing multiple appliances. The
centralized management feature provides increased reliability, flexibility, and scalability within your
network, allowing you to manage globally while complying with local policies.
A cluster is defined as a set of machines that share configuration information. Within the cluster,
machines (Cisco appliances) are divided into groups; every cluster will contain at least one group. A
given machine is a member of one and only one group. An administrator user can configure different
elements of the system on a cluster-wide, group-wide, or per-machine basis, enabling the segmentation
of Cisco appliances based on network, geography, business unit, or other logical relationships.
Clusters are implemented as a peer-to-peer architecture; there is no master/slave relationship within a
cluster. You may log into any machine to control and administer the cluster. (Some configuration
commands, however, are limited. See Restricted Commands, page 39-14.)
The user database is shared across all machines in the cluster. That is, there will be only one set of users
and one administrator user (with the associated passwords) for an entire cluster. All machines that join
a cluster will share a single administrator password which is referred to as the admin password of the
cluster.