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shafiq23
Staff & Editor
Staff & Editor
September 17, 2025

Technical Tip: How to rate limit source IP access to application URL within specified time

  • September 17, 2025
  • 0 replies
  • 290 views
Description This article describes how to configure a custom rule in FortiAppSec Cloud WAF to implement URL/API endpoint rate limiting. The goal of this rule is to limit the number of requests from a single client IP within a specified time.
Scope FortiAppSec Cloud WAF.
Solution

Requirement:
Period block source IP exceeds the rate limit within a specified time.

 

Configuration:

  1. Go to Advanced Applications -> Custom Rule and select Create Rule.
  2. Define the rule name and its operation (action).
  3. Select Add Filter to define the match conditions.

Source IP: '<IP-range>'.
URL: '/sample-URL'.
Occurrence: 10 times in 1 minute.

 

1.png

 

Expected result:
If there was a violation (11th request) within 1 minute, block the source IP for 60 seconds.

 

To verify the functionality of the custom rule, navigate to Threat Analytics -> Attack Logs and check for logs related to the custom rule name.

 

2.png

 

For more information, refer to the following document:

Custom Rule

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