Configure Network-layer DDoS Attack Protection via API

Configure the Cloudflare Network-layer DDoS Attack Protection managed ruleset by defining overrides at the account level using the Rulesets API.

Each account has the Network-layer DDoS Attack Protection managed ruleset enabled by default. This means that you do not need to deploy the managed ruleset to the ddos_l4 phase entry point ruleset explicitly. You only have to create a rule in the phase entry point to deploy the managed ruleset if you need to configure overrides.

​​ Configure an override for the Network-layer DDoS Attack Protection managed ruleset

You can define overrides at the ruleset, tag, and rule level for all managed rulesets.

When configuring the Network-layer DDoS Attack Protection managed ruleset, use overrides to define a different action or sensitivity from the default values. For more information on these rule parameters and the allowed values, refer to Managed ruleset parameters.

​​ Example

The following PUT example creates a new phase ruleset (or updates the existing one) for the ddos_l4 phase at the account level. The request includes several overrides to adjust the default behavior of the Network-layer DDoS Attack Protection managed ruleset. These overrides are the following:

• All rules of the Network-layer DDoS Attack Protection managed ruleset will have their sensitivity set to medium.
• All rules tagged with <TAG_NAME> will have their sensitivity set to low.
• The rule with ID <MANAGED_RULESET_RULE_ID> will use the block action.

The overrides apply to all packets matching the rule expression: ip.dst in { 1.1.1.0/24 }.

Request
curl --request PUT \
https://api.cloudflare.com/client/v4/accounts/{account_id}/rulesets/phases/ddos_l4/entrypoint \
--header "Authorization: Bearer <API_TOKEN>" \
--header "Content-Type: application/json" \
--data '{
  "description": "Define overrides for the Network-layer DDoS Attack Protection managed ruleset",
  "rules": [
    {
      "action": "execute",
      "expression": "ip.dst in { 1.1.1.0/24 }",
      "action_parameters": {
        "id": "<MANAGED_RULESET_ID>",
        "overrides": {
          "sensitivity_level": "medium",
          "categories": [
            {
              "category": "<TAG_NAME>",
              "sensitivity_level": "low"
            }
          ],
          "rules": [
            {
              "id": "<MANAGED_RULESET_RULE_ID>",
              "action": "block"
            }
          ]
        }
      }
    }
  ]
}'

The response returns the created (or updated) phase entry point ruleset.

{
  "result": {
    "id": "<PHASE_ENTRY_POINT_RULESET_ID>",
    "name": "default",
    "description": "Define overrides for the Network-layer DDoS Attack Protection managed ruleset",
    "kind": "root",
    "version": "1",
    "rules": [
      {
        "id": "<RULE_ID>",
        "version": "1",
        "action": "execute",
        "action_parameters": {
          "id": "<MANAGED_RULESET_ID>",
          "version": "latest",
          "overrides": {
            "categories": [
              {
                "category": "<TAG_NAME>",
                "sensitivity_level": "low"
              }
            ],
            "rules": [
              {
                "id": "<MANAGED_RULESET_RULE_ID>",
                "action": "block"
              }
            ],
            "sensitivity_level": "medium"
          }
        },
        "expression": "ip.dst in { 1.1.1.0/24 }",
        "last_updated": "2021-08-16T04:14:47.977741Z",
        "ref": "<RULE_REF>",
        "enabled": true
      }
    ],
    "last_updated": "2021-08-16T04:14:47.977741Z",
    "phase": "ddos_l4"
  }
}

For more information on defining overrides for managed rulesets using the Rulesets API, refer to Override a managed ruleset.