You can create your own WAF rules with the ability to block, rate-limit, and tag requests.


For each type of rule, you can supply different types of conditions that must be met such as Path, IP Address, and Request Header. These conditions can be grouped together to specify if all or if just one needs to be true, and you can chain together multiple groups to create a ruleset. For example, the block rule below will block all requests that originate from the IP Address



For Tag rules, you must specify the Tag Name that you want applied to any requests that match the condition set. The tag rule below will tag all requests to the login endpoint that return 401 status code with Unauthorized_Login.


Rate Limit

For Rate Limit rules, you can specify the type of identifier to be used to determine the uniqueness of the requests. The possible identifiers are IP Address, User, and Session; you can select any combination of the three. In the Action section, you can specify the number of requests (Threshold) that must match the condition set within a certain period of time (Interval) before Metlo starts to block any subsequent requests from that unique identifier for the next x hours/minutes/seconds (Duration). The rate-limit rule below will block any unique IP addresses that attempt more than 10 login requests within a minute for the next 10 minutes.