Edge Security Acceleration:Rules

Simple configuration examples

Rule configuration structure

When a request reaches an ESA node, ESA filters and processes the request according to your rule configuration.

Every ESA rule configuration includes two parts:

Rule configuration = Rule expression + Action

You can configure a rule expression to filter requests and an action to execute operations on matched requests. The rule expression syntax is consistent for all rule-related configurations in ESA. This lets you reuse a rule configuration method from one feature in other features. For more information about how to create and deploy rules, see Rule expression structure.

Rule Precedence

• Rule configurations take precedence over global settings: For the same feature, settings defined in a rule override global settings. This lets you apply general configurations broadly while using rules to customize behavior for specific requests.

  

  For example, consider the edge time-to-live (TTL): If you configure the Edge TTL to 12 hours in Global Configuration – Edge Cache TTL and configure the TTL for resources under /content to 30 days in Rules – Configure Edge Cache TTL, the edge node adjusts the cache TTL for that resource to 30 days when the requested resource path is under /content. For resources whose request paths are not under /content, the edge node uses the global TTL of 12 hours.

  

• Rules higher in the list have higher priority: For the same rule type, ESA executes rules from top to bottom. If a request matches multiple rules, you can drag the button to move the rule that you want to prioritize higher in the list.

  Note

  Different plans support different features and numbers of rules. For more information about rule quotas by plan type, see Rule and plan quotas.

  Take cache rules as an example. Suppose you have these two rules:

  Rule 1: Resources under the /content path expire after 30 days.

  Rule 2: Files with the .jpg suffix are cached for 60 days.

  • In the following figure, Rule 1 appears above Rule 2.

    

    The cache expiration times on edge nodes are:

    Sample URL	Under /content path	.jpg suffix	Cache expiration time
    https://example.com/content/static/pic.jpg			30 days
    https://example.com/content/static/book.txt		×	30 days
    https://example.com/static/pic.jpg	×		60 days
    https://example.com/static/res/book.text	×	×	Do not cache

  • In the following figure, Rule 2 appears above Rule 1.

    The cache expiration times on edge nodes are:

    Sample URI	Under /content path	.jpg suffix	Cache expiration time
    https://example.com/content/static/pic.jpg			60 days
    https://example.com/content/static/book.txt		×	30 days
    https://example.com/static/pic.jpg	×		60 days
    https://example.com/static/res/book.text	×	×	Do not cache

Feature availability by plan