Hello @Dots ,
Welcome to Microsoft Q&A Platform. Thank you for reaching out & hope you are doing well.
Unfortunately, Application Gateway WAF does not have a way to rate limit incoming connections.
Rate-limiting, geo-filtering, and Azure managed Default Rule Set rules are supported only with WAF on Azure Front Door.
Refer : https://video2.skills-academy.com/en-us/azure/web-application-firewall/afds/waf-faq#do-you-support-same-waf-features-in-all-integrated-platforms-
If you wish you may upvote the feedback in the below forum requesting this feature. All the feedback you share in these forums will be monitored and reviewed by the Microsoft engineering teams responsible for building Azure.
https://feedback.azure.com/d365community/idea/261a91eb-8326-ec11-b6e6-000d3a4f0789
Currently, you can only configure a WAF rate limit rule on Azure Front Door:
https://video2.skills-academy.com/en-us/azure/web-application-firewall/afds/waf-front-door-rate-limit-powershell
Kindly let us know if the above helps or you need further assistance on this issue.
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