dualstack-envoy.yaml

admin:
  access_log_path: /tmp/admin_access.log
  address:
    socket_address:
      protocol: TCP
      address: 127.0.0.1
      port_value: 9901
static_resources:
  listeners:
  - name: dual_stack_listener
    reuse_port: false
    addresses:
    - socket_address:
        protocol: TCP
        address: "172.41.3.14"        
        port_value: 13333
    - socket_address:
        protocol: TCP
        address: "2001:db8:85a3::1"        
        port_value: 13334
    filter_chains:
    - filters:
      - name: envoy.filters.network.http_connection_manager
        typed_config:
          "@type": type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager
          stat_prefix: ingress_http
          route_config:
            name: local_route
            virtual_hosts:
            - name: local_service
              domains: ["*"]
              routes:
              - match:
                  prefix: "/"
                route:
                  cluster: dual_stack_cluster
            request_headers_to_add:
            - header:
                key: x-downstream-local-address
                value: "%DOWNSTREAM_LOCAL_ADDRESS_WITHOUT_PORT%"
          http_filters:
          - name: envoy.filters.http.header_to_metadata
            typed_config:
              "@type": type.googleapis.com/envoy.extensions.filters.http.header_to_metadata.v3.Config
              request_rules:
              - header: x-downstream-local-address
                on_header_present:
                  metadata_namespace: envoy.lb
                  key: ipfamily
                  type: STRING
                remove: true
          - name: envoy.filters.http.router
            typed_config:
              "@type": type.googleapis.com/envoy.extensions.filters.http.router.v3.Router
  clusters:
  - name: dual_stack_cluster
    connect_timeout: 0.25s
    type: STATIC
    lb_policy: round_robin
    # This is subset loadbanacer config.
    lb_subset_config:
      fallback_policy: NO_FALLBACK
      default_subset:
        stage: prod
      subset_selectors:
      - keys:
        - ipfamily
    protocol_selection: USE_DOWNSTREAM_PROTOCOL
    http2_protocol_options: {}
    dns_lookup_family: ALL
    load_assignment:
      cluster_name: dual_stack_cluster
      endpoints:
      # So we can put ipv4 and ipv6 endpoints in single cluster but with different metadata
      - lb_endpoints:
        - endpoint:
            address:
              socket_address:
                address: 127.0.0.1
                port_value: 33333
          metadata:
            filter_metadata:
              envoy.lb:
                ipfamily: '172.41.3.14'
        - endpoint:
            address:
              socket_address:
                address: ::1
                port_value: 33334
          metadata:
            filter_metadata:
              envoy.lb:
                ipfamily: '2001:db8:85a3::1'