JUNOS Enterprise Switching

Chapter 8. Routing Policy and Firewall Filters

Routing policy and firewall filters serve very different purposes, but because they share a common structure, they can be grouped together. A shot of tequila can be used to celebrate a birthday or a team win, or to block out the birthday or team loss. Either way, liquor is a common tool (or language) that can lead to very different results.

Once you understand the framework of policy language, you can switch between policies and filters seamlessly, concentrating on the application needed and not the syntax.

This chapter is divided into two sections. The first half discusses policy and includes the following topics:

• Policy overview and import and export policy

• Policy components (terms, match conditions, actions, and policy chains)

• Route filters

• Testing and monitoring policy

• Policy case study

The second half of this chapter discusses firewall filters:

• Firewall filter overview

• Firewall filter processing

• Firewall filter monitoring

Routing Policy

This section details JUNOS software routing policy operation and configuration. The actual application of policy to solve some specific networking requirement is generally left to the protocol to which the policy is applied. These particular applications are discussed in various sections throughout the book. You configure policy-related options and statements at the [edit policy-options] hierarchy. Routing policy and firewall filters have a similar syntax in JUNOS software. The first deals with routes in the ...