Configure DDoS managed rulesets

This page provides examples of configuring DDoS managed rulesets in your zone or account using Terraform. It covers the following configurations:

• Configure HTTP DDoS Attack Protection
• Configure Network-layer DDoS Attack Protection

DDoS managed rulesets are always enabled. Depending on your Cloudflare services, you may be able to adjust their behavior.

For more information on DDoS managed rulesets, refer to Managed rulesets in the Cloudflare DDoS Protection documentation. For more information on deploying and configuring rulesets using the Rulesets API, refer to Work with managed rulesets in the Ruleset Engine documentation.

​​ Before you start

​​ Obtain the necessary account, zone, and managed ruleset IDs

The Terraform configurations provided in this page need the zone ID (or account ID) of the zone/account where you will deploy the managed rulesets.

• To retrieve the list of accounts you have access to, including their IDs, use the List accounts API operation.
• To retrieve the list of zones you have access to, including their IDs, use the List zones API operation.

The deployment of managed rulesets via Terraform requires that you use the ruleset IDs. To find the IDs of managed rulesets, use the List account rulesets API operation. The response will include the description and IDs of existing managed rulesets.

​​ (Optional) Delete existing rulesets to start from scratch

Terraform assumes that it has complete control over account and zone rulesets. If you already have rulesets configured in your account or zone, do one of the following:

• Import existing rulesets to Terraform using the cf-terraforming tool. Recent versions of the tool can generate resource definitions for existing rulesets and import their configuration to Terraform state.
• Start from scratch by deleting existing rulesets (account and zone rulesets with "kind": "root" and "kind": "zone", respectively) and then defining your rulesets configuration in Terraform.

​​ Configure HTTP DDoS Attack Protection

This example configures HTTP DDoS Attack Protection for a zone using Terraform, changing the sensitivity level of rule with ID fdfdac75430c4c47a959592f0aa5e68a to low.

resource "cloudflare_ruleset" "zone_level_http_ddos_config" {
  zone_id     = "<ZONE_ID>"
  name        = "HTTP DDoS Attack Protection entry point ruleset"
  description = ""
  kind        = "zone"
  phase       = "ddos_l7"

  rules {
    action = "execute"
    action_parameters {
      id = "4d21379b4f9f4bb088e0729962c8b3cf"
      overrides {
        rules {
          # Rule: HTTP requests with unusual HTTP headers or URI path (signature #11).
          id = "fdfdac75430c4c47a959592f0aa5e68a"
          sensitivity_level = "low"
        }
      }
    }
    expression = "true"
    description = "Override the HTTP DDoS Attack Protection managed ruleset"
    enabled = true
  }
}

For more information about HTTP DDoS Attack Protection, refer to HTTP DDoS Attack Protection managed ruleset.

​​ Configure Network-layer DDoS Attack Protection

This example configures Network-layer DDoS Attack Protection for an account using Terraform, changing the sensitivity level of rule with ID 599dab0942ff4898ac1b7797e954e98b to low using an override.

resource "cloudflare_ruleset" "account_level_network_ddos_config" {
  account_id  = "<ACCOUNT_ID>"
  name        = "Network-layer DDoS Attack Protection entry point ruleset"
  description = ""
  kind        = "root"
  phase       = "ddos_l4"

  rules {
    action = "execute"
    action_parameters {
      id = "3b64149bfa6e4220bbbc2bd6db589552"
      overrides {
        rules {
          # Rule: Generic high-volume UDP traffic flows.
          id = "599dab0942ff4898ac1b7797e954e98b"
          sensitivity_level = "low"
        }
      }
    }
    expression = "ip.dst in { 192.0.2.0/24 }"
    description = "Override the HTTP DDoS Attack Protection managed ruleset"
    enabled = true
  }
}

For more information about Network-layer DDoS Attack Protection, refer to Network-layer DDoS Attack Protection managed ruleset.