Architecture and Deployment

What this chapter covers

This chapter explains how a Cisco ISE deployment is built from nodes and the roles they play.

It starts with the personas that split the work between nodes. It then covers the deployment models, the form factors and sizing, and ends with zero touch provisioning for fast, repeatable builds.

Everything later in the guide depends on this layout. Policies, guest portals, posture and device administration all run on the nodes described here.

Expect to meet the personas by name in many later questions. When a later page says that a node answers a request, it means a Policy Service Node. When it says that you change a setting, it means you do it on the primary administration node.

How the topics fit together

You first decide which personas exist, then how many nodes carry them, then how to build those nodes.

Each topic answers one question:

• Personas: what does each role do, and how do I register a node?
• Deployment options: how many nodes do I need, and how do I keep service running if one fails?
• Sizing: how big must each appliance or virtual machine be?
• Zero touch provisioning: how do I bring up new nodes and devices without typing every setting?

The order matters. A small lab can stay on one node, but a production design needs more than one, and the choice of form factor follows from the load you expect. Zero touch provisioning then lets you repeat the build for each extra node.

How to use these pages

Each topic page has the same shape, so you can skim for what you need.

• What it is: the idea in plain words.
• How it works: the mechanism, with diagrams and example commands.
• What to remember for the exam: the facts to memorise.
• Common mistakes: the classic traps.
• Check yourself: three questions to test your understanding.

If you have access to a lab, install a standalone node and then register a second node. Seeing the deployment page change is the quickest way to make the personas stick.