Customize EnvoyProxy

  11 minute read  

Envoy Gateway provides an EnvoyProxy CRD that can be linked to the ParametersRef in a Gateway and GatewayClass, allowing cluster admins to customize the managed EnvoyProxy Deployment and Service. To learn more about GatewayClass and ParametersRef, please refer to Gateway API documentation.

Prerequisites

Follow the steps from the Quickstart task to install Envoy Gateway and the example manifest. Before proceeding, you should be able to query the example backend using HTTP.

Verify the Gateway status:

kubectl get gateway/eg -o yaml

egctl x status gateway -v

Before you start, you need to add Infrastructure.ParametersRef in Gateway, and refer to EnvoyProxy Config: Note: MergeGateways cannot be set to true in your EnvoyProxy config if attaching to the Gateway.

cat <<EOF | kubectl apply -f -
apiVersion: gateway.networking.k8s.io/v1
kind: Gateway
metadata:
  name: eg
spec:
  gatewayClassName: eg
  infrastructure:
    parametersRef:
      group: gateway.envoyproxy.io
      kind: EnvoyProxy
      name: custom-proxy-config
  listeners:
    - name: http
      protocol: HTTP
      port: 80
EOF

Save and apply the following resource to your cluster:

---
apiVersion: gateway.networking.k8s.io/v1
kind: Gateway
metadata:
  name: eg
spec:
  gatewayClassName: eg
  infrastructure:
    parametersRef:
      group: gateway.envoyproxy.io
      kind: EnvoyProxy
      name: custom-proxy-config
  listeners:
    - name: http
      protocol: HTTP
      port: 80

You can also attach the EnvoyProxy resource to the GatewayClass using the parametersRef field. This configuration is discouraged if you plan on creating multiple Gateways linking to the same GatewayClass and would like different infrastructure configurations for each of them.

cat <<EOF | kubectl apply -f -
apiVersion: gateway.networking.k8s.io/v1
kind: GatewayClass
metadata:
  name: eg
spec:
  controllerName: gateway.envoyproxy.io/gatewayclass-controller
  parametersRef:
    group: gateway.envoyproxy.io
    kind: EnvoyProxy
    name: custom-proxy-config
    namespace: default
EOF

Save and apply the following resource to your cluster:

---
apiVersion: gateway.networking.k8s.io/v1
kind: GatewayClass
metadata:
  name: eg
spec:
  controllerName: gateway.envoyproxy.io/gatewayclass-controller
  parametersRef:
    group: gateway.envoyproxy.io
    kind: EnvoyProxy
    name: custom-proxy-config
    namespace: default

Customize EnvoyProxy Deployment Replicas

You can customize the EnvoyProxy Deployment Replicas via EnvoyProxy Config like:

cat <<EOF | kubectl apply -f -
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyDeployment:
        replicas: 2
EOF

Save and apply the following resource to your cluster:

---
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyDeployment:
        replicas: 2

After you apply the config, you should see the replicas of envoyproxy changes to 2. And also you can dynamically change the value.

kubectl get deployment -l gateway.envoyproxy.io/owning-gateway-name=eg -n envoy-gateway-system

Customize EnvoyProxy Image

You can customize the EnvoyProxy Image via EnvoyProxy Config like:

cat <<EOF | kubectl apply -f -
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyDeployment:
        container:
          image: envoyproxy/envoy:v1.25-latest
EOF

Save and apply the following resource to your cluster:

---
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyDeployment:
        container:
          image: envoyproxy/envoy:v1.25-latest

After applying the config, you can get the deployment image, and see it has changed.

Customize EnvoyProxy Pod Annotations

You can customize the EnvoyProxy Pod Annotations via EnvoyProxy Config like:

cat <<EOF | kubectl apply -f -
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyDeployment:
        pod:
          annotations:
            custom1: deploy-annotation1
            custom2: deploy-annotation2
EOF

Save and apply the following resource to your cluster:

---
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyDeployment:
        pod:
          annotations:
            custom1: deploy-annotation1
            custom2: deploy-annotation2

After applying the config, you can get the envoyproxy pods, and see new annotations has been added.

Customize EnvoyProxy Deployment Resources

You can customize the EnvoyProxy Deployment Resources via EnvoyProxy Config like:

cat <<EOF | kubectl apply -f -
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyDeployment:
        container:
          resources:
            requests:
              cpu: 150m
              memory: 640Mi
            limits:
              cpu: 500m
              memory: 1Gi
EOF

Save and apply the following resource to your cluster:

---
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyDeployment:
        container:
          resources:
            requests:
              cpu: 150m
              memory: 640Mi
            limits:
              cpu: 500m
              memory: 1Gi

Customize EnvoyProxy Deployment Env

You can customize the EnvoyProxy Deployment Env via EnvoyProxy Config like:

cat <<EOF | kubectl apply -f -
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyDeployment:
        container:
          env:
          - name: env_a
            value: env_a_value
          - name: env_b
            value: env_b_value
EOF

Save and apply the following resource to your cluster:

---
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyDeployment:
        container:
          env:
          - name: env_a
            value: env_a_value
          - name: env_b
            value: env_b_value

Envoy Gateway has provided two initial env ENVOY_GATEWAY_NAMESPACE and ENVOY_POD_NAME for envoyproxy container.

After applying the config, you can get the envoyproxy deployment, and see resources has been changed.

Customize EnvoyProxy Deployment Volumes or VolumeMounts

You can customize the EnvoyProxy Deployment Volumes or VolumeMounts via EnvoyProxy Config like:

cat <<EOF | kubectl apply -f -
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyDeployment:
        container:
          volumeMounts:
          - mountPath: /certs
            name: certs
            readOnly: true
        pod:
          volumes:
          - name: certs
            secret:
              secretName: envoy-cert
EOF

Save and apply the following resource to your cluster:

---
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyDeployment:
        container:
          volumeMounts:
          - mountPath: /certs
            name: certs
            readOnly: true
        pod:
          volumes:
          - name: certs
            secret:
              secretName: envoy-cert

After applying the config, you can get the envoyproxy deployment, and see resources has been changed.

Customize EnvoyProxy Service Annotations

You can customize the EnvoyProxy Service Annotations via EnvoyProxy Config like:

cat <<EOF | kubectl apply -f -
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyService:
        annotations:
          custom1: svc-annotation1
          custom2: svc-annotation2
EOF

Save and apply the following resource to your cluster:

---
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyService:
        annotations:
          custom1: svc-annotation1
          custom2: svc-annotation2

After applying the config, you can get the envoyproxy service, and see annotations has been added.

Customize EnvoyProxy Bootstrap Config

You can customize the EnvoyProxy bootstrap config via EnvoyProxy Config. There are two ways to customize it:

  • Replace: the whole bootstrap config will be replaced by the config you provided.
  • Merge: the config you provided will be merged into the default bootstrap config.
cat <<EOF | kubectl apply -f -
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default 
spec:
  bootstrap:
    type: Replace
    value: |
      admin:
        access_log:
        - name: envoy.access_loggers.file
          typed_config:
            "@type": type.googleapis.com/envoy.extensions.access_loggers.file.v3.FileAccessLog
            path: /dev/null
        address:
          socket_address:
            address: 127.0.0.1
            port_value: 20000
      dynamic_resources:
        ads_config:
          api_type: DELTA_GRPC
          transport_api_version: V3
          grpc_services:
          - envoy_grpc:
              cluster_name: xds_cluster
          set_node_on_first_message_only: true
        lds_config:
          ads: {}
          resource_api_version: V3
        cds_config:
          ads: {}
          resource_api_version: V3
      static_resources:
        clusters:
        - connect_timeout: 10s
          load_assignment:
            cluster_name: xds_cluster
            endpoints:
            - lb_endpoints:
              - endpoint:
                  address:
                    socket_address:
                      address: envoy-gateway
                      port_value: 18000
          typed_extension_protocol_options:
            "envoy.extensions.upstreams.http.v3.HttpProtocolOptions":
               "@type": "type.googleapis.com/envoy.extensions.upstreams.http.v3.HttpProtocolOptions"
               "explicit_http_config":
                 "http2_protocol_options": {}
          name: xds_cluster
          type: STRICT_DNS
          transport_socket:
            name: envoy.transport_sockets.tls
            typed_config:
              "@type": type.googleapis.com/envoy.extensions.transport_sockets.tls.v3.UpstreamTlsContext
              common_tls_context:
                tls_params:
                  tls_maximum_protocol_version: TLSv1_3
                tls_certificate_sds_secret_configs:
                - name: xds_certificate
                  sds_config:
                    path_config_source:
                      path: "/sds/xds-certificate.json"
                    resource_api_version: V3
                validation_context_sds_secret_config:
                  name: xds_trusted_ca
                  sds_config:
                    path_config_source:
                      path: "/sds/xds-trusted-ca.json"
                    resource_api_version: V3
      layered_runtime:
        layers:
        - name: runtime-0
          rtds_layer:
            rtds_config:
              ads: {}
              resource_api_version: V3
            name: runtime-0
EOF

Save and apply the following resource to your cluster:

---
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  bootstrap:
    type: Replace
    value: |
      admin:
        access_log:
        - name: envoy.access_loggers.file
          typed_config:
            "@type": type.googleapis.com/envoy.extensions.access_loggers.file.v3.FileAccessLog
            path: /dev/null
        address:
          socket_address:
            address: 127.0.0.1
            port_value: 20000
      dynamic_resources:
        ads_config:
          api_type: DELTA_GRPC
          transport_api_version: V3
          grpc_services:
          - envoy_grpc:
              cluster_name: xds_cluster
          set_node_on_first_message_only: true
        lds_config:
          ads: {}
          resource_api_version: V3
        cds_config:
          ads: {}
          resource_api_version: V3
      static_resources:
        clusters:
        - connect_timeout: 10s
          load_assignment:
            cluster_name: xds_cluster
            endpoints:
            - lb_endpoints:
              - endpoint:
                  address:
                    socket_address:
                      address: envoy-gateway
                      port_value: 18000
          typed_extension_protocol_options:
            "envoy.extensions.upstreams.http.v3.HttpProtocolOptions":
               "@type": "type.googleapis.com/envoy.extensions.upstreams.http.v3.HttpProtocolOptions"
               "explicit_http_config":
                 "http2_protocol_options": {}
          name: xds_cluster
          type: STRICT_DNS
          transport_socket:
            name: envoy.transport_sockets.tls
            typed_config:
              "@type": type.googleapis.com/envoy.extensions.transport_sockets.tls.v3.UpstreamTlsContext
              common_tls_context:
                tls_params:
                  tls_maximum_protocol_version: TLSv1_3
                tls_certificate_sds_secret_configs:
                - name: xds_certificate
                  sds_config:
                    path_config_source:
                      path: "/sds/xds-certificate.json"
                    resource_api_version: V3
                validation_context_sds_secret_config:
                  name: xds_trusted_ca
                  sds_config:
                    path_config_source:
                      path: "/sds/xds-trusted-ca.json"
                    resource_api_version: V3
      layered_runtime:
        layers:
        - name: runtime-0
          rtds_layer:
            rtds_config:
              ads: {}
              resource_api_version: V3
            name: runtime-0

You can use egctl translate to get the default xDS Bootstrap configuration used by Envoy Gateway.

After applying the config, the bootstrap config will be overridden by the new config you provided. Any errors in the configuration will be surfaced as status within the GatewayClass resource. You can also validate this configuration using egctl translate.

Customize EnvoyProxy Horizontal Pod Autoscaler

You can enable Horizontal Pod Autoscaler for EnvoyProxy Deployment. However, before enabling the HPA for EnvoyProxy, please ensure that the metrics-server component is installed in the cluster.

Once confirmed, you can apply it via EnvoyProxy Config as shown below:

cat <<EOF | kubectl apply -f -
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default 
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyHpa:
        minReplicas: 2
        maxReplicas: 10
        metrics:
          - resource:
              name: cpu
              target:
                averageUtilization: 60
                type: Utilization
            type: Resource
EOF

Save and apply the following resource to your cluster:

---
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default 
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyHpa:
        minReplicas: 2
        maxReplicas: 10
        metrics:
          - resource:
              name: cpu
              target:
                averageUtilization: 60
                type: Utilization
            type: Resource

After applying the config, the EnvoyProxy HPA (Horizontal Pod Autoscaler) is generated. However, upon activating the EnvoyProxy’s HPA, the Envoy Gateway will no longer reference the replicas field specified in the envoyDeployment, as outlined here.

Customize EnvoyProxy Command line options

You can customize the EnvoyProxy Command line options via spec.extraArgs in EnvoyProxy Config. For example, the following configuration will add --disable-extensions arg in order to disable envoy.access_loggers/envoy.access_loggers.wasm extension:

cat <<EOF | kubectl apply -f -
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default 
spec:
  extraArgs:
    - --disable-extensions envoy.access_loggers/envoy.access_loggers.wasm 
EOF

Save and apply the following resource to your cluster:

---
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default 
spec:
  extraArgs:
    - --disable-extensions envoy.access_loggers/envoy.access_loggers.wasm

Customize EnvoyProxy with Patches

You can customize the EnvoyProxy using patches.

Patching Deployment for EnvoyProxy

For example, the following configuration will add resource limits to the envoy and the shutdown-manager containers in the envoyproxy deployment:

cat <<EOF | kubectl apply -f -
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: eg
  namespace: default 
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyDeployment:
        patch:
          type: StrategicMerge
          value:
            spec:
              template:
                spec:
                  containers:
                  - name: envoy
                    resources:
                      limits:
                        cpu: 500m
                        memory: 1024Mi
                  - name: shutdown-manager
                    resources:
                      limits:
                        cpu: 200m
                        memory: 1024Mi
EOF

Save and apply the following resource to your cluster:

---
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: eg
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyDeployment:
        patch:
          type: StrategicMerge
          value:
            spec:
              template:
                spec:
                  containers:
                  - name: envoy
                    resources:
                      limits:
                        cpu: 500m
                        memory: 1024Mi
                  - name: shutdown-manager
                    resources:
                      limits:
                        cpu: 200m
                        memory: 1024Mi

After applying the configuration, you will see the change in both containers in the envoyproxy deployment.

Patching Service for EnvoyProxy

For example, the following configuration will add an annotation for the envoyproxy service:

cat <<EOF | kubectl apply -f -
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: eg
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyService:
        patch:
          type: StrategicMerge
          value:
            metadata:
              annotations:
                custom-annotation: foobar
EOF

Save and apply the following resource to your cluster:

---
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: eg
  namespace: default
spec:
  provider:
    type: Kubernetes
    kubernetes:
      envoyService:
        patch:
          type: StrategicMerge
          value:
            metadata:
              annotations:
                custom-annotation: foobar

After applying the configuration, you will see the custom-annotation: foobar has been added to the envoyproxy service.

Customize Filter Order

Under the hood, Envoy Gateway uses a series of Envoy HTTP filters to process HTTP requests and responses, and to apply various policies.

By default, Envoy Gateway applies the following filters in the order shown:

  • envoy.filters.http.fault
  • envoy.filters.http.cors
  • envoy.filters.http.ext_authz
  • envoy.filters.http.basic_authn
  • envoy.filters.http.oauth2
  • envoy.filters.http.jwt_authn
  • envoy.filters.http.ext_proc
  • envoy.filters.http.wasm
  • envoy.filters.http.rbac
  • envoy.filters.http.local_ratelimit
  • envoy.filters.http.ratelimit
  • envoy.filters.http.router

The default order in which these filters are applied is opinionated and may not suit all use cases. To address this, Envoy Gateway allows you to adjust the execution order of these filters with the filterOrder field in the EnvoyProxy resource.

filterOrder is a list of customized filter order configurations. Each configuration can specify a filter name and a filter to place it before or after. These configurations are applied in the order they are listed. If a filter occurs in multiple configurations, the final order is the result of applying all these configurations in order. To avoid conflicts, it is recommended to only specify one configuration per filter.

For example, the following configuration moves the envoy.filters.http.wasm filter before the envoy.filters.http.jwt_authn filter and the envoy.filters.http.cors filter after the envoy.filters.http.basic_authn filter:

cat <<EOF | kubectl apply -f -
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  filterOrder:
    - name: envoy.filters.http.wasm
      before: envoy.filters.http.jwt_authn
    - name: envoy.filters.http.cors
      after: envoy.filters.http.basic_authn
EOF

Save and apply the following resource to your cluster:

---
apiVersion: gateway.envoyproxy.io/v1alpha1
kind: EnvoyProxy
metadata:
  name: custom-proxy-config
  namespace: default
spec:
  filterOrder:
    - name: envoy.filters.http.wasm
      before: envoy.filters.http.jwt_authn
    - name: envoy.filters.http.cors
      after: envoy.filters.http.basic_authn

Last modified December 20, 2024: chore: fix typo (#4958) (2a10d47)