External Authorization

The external authorization HTTP filter calls an external gRPC service to check if the incoming HTTP request is authorized or not. If the request is deemed unauthorized then the request will be denied with 403 (Forbidden) response.


It is recommended that this filter is configured first in the filter chain so that requests are authorized prior to the rest of filters processing the request.

The content of the requests that are passed to an authorization service is specified by CheckRequest.

The HTTP filter, using a gRPC service, can be configured as follows. You can see all the configuration options at HTTP filter.


A sample filter configuration could be:

  - name: envoy.ext_authz
           cluster_name: ext-authz

  - name: ext-authz
    type: static
    http2_protocol_options: {}
      - socket_address: { address:, port_value: 10003 }


The HTTP filter outputs statistics in the cluster.<route target cluster>.ext_authz. namespace.

Name Type Description
ok Counter Total responses from the filter.
error Counter Total errors contacting the external service.
denied Counter Total responses from the authorizations service that were to deny the traffic.
failure_mode_allow Counter Total requests that were error(s) but were allowed through because of failure_mode_allow set to true.