WAN Rules establish the conditions for applying a specific WAN Policy. By associating a WAN Rule to a WAN Policy, you are defining the optimal route for traffic that meets the rule condition.
If you manage multiple appliances, you can configure a common set of WAN Rules that you can synchronize to appliances in the same SD-WAN Network. See Configuring WAN Rules for Micro Edge in ETM Dashboard.
Common rule conditions include:
- An application
- An application category
- An IP address or subnet
- A hostname (DNS hint)
- A protocol or port number
- An interface zone
For example, a WAN Rule may specify that for the Microsoft Teams application, use the WAN Policy that sends sessions to the link with the lowest latency.
Note: Conditions based on application criteria rely on a cloud component to "infer" the application based on specific details of the first packet in the session. See Application identification in Micro Edge.
For a complete description of Rule Syntax and Conditions refer to Conditions Syntax in Micro Edge rules.
Creating a WAN Rule
To create a WAN Rule:
- Go to Settings -> Routing -> WAN Rules and click New Rule.
- Enter a description (e.g. messaging apps).
- Click Add Condition, select a condition type (e.g. Application Category).
- Enter a Value (e.g. Messaging). Note this option autocompletes as you type.
Note: you can add multiple conditions to the rule.
- Under Action, choose a WAN Policy to determine where to route traffic meeting the rule.
- Review the Summary and click Save.
Sorting WAN Rules
WAN rules operate just like regular rules as described in the Rules documentation. This means that rules are evaluated from top to bottom, and the first rule that successfully meets the condition is processed.
Note: If the path defined by the WAN Policy is not available and cannot be used, the rule is skipped and subsequent rules are evaluated.Follow