Route Maps🔗

A Route Map is a policy tool that allows administrators to override automated path selections and force specific traffic flows to follow predetermined routes. The purpose of using route maps is to direct traffic toward paths that are faster, more efficient, and experience less packet loss than the automatically selected routes.

Route-maps are used to filter or modify routes based on many possible criteria. Route-maps are composed of one or more Route-map Clauses. Each clause uses a filter to select the relevant routes (match criteria). Once selected, parameters of the routes can be modified with Set commands.

Beware of Misconfigurations

It is important that network administrators are deeply familiar with BGP and Route Map concepts before manipulating settings. Misconfiguration can lead to routing loops, traffic disruption, service outages, security vulnerabilities, and performance degradation.

Route Map Composition🔗

Route Maps are composed of:

Route Map Clause(s) – This is a statement or rule within the route map that is composed of permit or deny match conditions, including matches to Lists.
Access Control List(s) – A collection of Conditions or criteria that define specific attributes to match against network traffic. (ACLs are used to match 5 tuple)
Condition(s) – These are individual factors such as IP addresses, destination IP addresses or protocol types.

Creating Route Maps🔗

Double-click Templates. Click Route Maps. ()
Click the Add Route Map () button.
Enter the name of the new route-map (). Click Create Route Map.
Click the Enable switch. ()
Double-click the input field that says Choose a Route Map Clause and select Create New Route Map Clause in the select box. ()
Enable the checkbox next to the form field. ()
Click the Edit Mode Save button. ()

Adding Multiple Clauses

To create and enable multiple Route Map Clauses, click the Add Row button.

Route Maps Clauses🔗

Route Map Clauses are composed of permit or deny match conditions, including matches to Lists in Match Fields.

Create a Route Map Clause🔗

Double-click Template and then click Route Map Clauses. ()
Click the Add Route Map Clause () button.
In the window that appears type the name of the Route Map Clause and click Create Route Map Clause. ()

Match Conditions in a Route Map Clause🔗

Double-click Templates and click Route Map Clauses.
In the fields that appears create a new Match field by clicking the Select a Match Field to Add.
In the window that appears, select a choice from the drop down menu.

Access Control Lists🔗

An access control list (ACL) is a collection of conditions to match specific attributes of network traffic. These conditions can include source IP addresses, destination IP addresses, protocol type and other data.

Creating an Access Control List🔗

AS Path Lists🔗

AS Path Lists allow a route map to select routes with a specific AS number in the path using regex.

Creating an AS Path List🔗

Double-click Templates and click the AS Path Access List tile.
Click the Add AS Path Access List () button.
Enter a name for the list and click Create ne As Path Access List.
Set the conditions for the list. ()
In the Edit Mode prompt click the Save button () .

Community Lists🔗

Community Lists allow a route map to select routes originating from a specific community.

Creating a Community List🔗

Double-click Templates and click Community List.
Click the Add a New Community List button.
Enter a name for the list and click Create Community List. ()
Set the conditions for the list.
In the Edit Mode prompt click the Save button () .

Extended Community Lists🔗

An Extended Community List is a filter that controls how routes are shared between separate virtual networks (VRFs) on a router.

Creating an Extended Community List🔗

Double-click Templates and click Extended Community List.
Click the Add a New Extended Community List button.
Enter a name for the list and click Create Extended Community List. ()
Set the conditions for the list.
In the Edit Mode prompt click the Save button () .