Service Mesh

MeshConfig

MeshConfig defines mesh-wide variables shared by all Envoy instances in the Istio service mesh.

Field Type Description
mixerAddress string Address of the mixer service (e.g. istio-mixer:9090). Empty value disables Mixer checks and telemetry.
disablePolicyChecks bool Disable policy checks by the mixer service. Metrics will still be reported to the mixer for HTTP requests and TCP connections. Default is false, i.e. mixer policy check is enabled by default.
proxyListenPort int32 Port on which Envoy should listen for incoming connections from other services.
proxyHttpPort int32 Port on which Envoy should listen for HTTP PROXY requests if set.
connectTimeout Duration Connection timeout used by Envoy. (MUST BE >=1ms)
ingressClass string Class of ingress resources to be processed by Istio ingress controller. This corresponds to the value of "kubernetes.io/ingress.class" annotation.
ingressService string Name of the kubernetes service used for the istio ingress controller.
ingressControllerMode IngressControllerMode Defines whether to use Istio ingress controller for annotated or all ingress resources.
authPolicy AuthPolicy Authentication policy defines the global switch to control authentication for Envoy-to-Envoy communication.
rdsRefreshDelay Duration Polling interval for RDS (MUST BE >=1ms)
enableTracing bool Flag to control generation of trace spans and request IDs. Requires a trace span collector defined in the proxy configuration.
accessLogFile string File address for the proxy access log (e.g. /dev/stdout). Empty value disables access logging.
defaultConfig ProxyConfig Default proxy config used by the proxy injection mechanism operating in the mesh (e.g. Kubernetes admission controller) In case of Kubernetes, the proxy config is applied once during the injection process, and remain constant for the duration of the pod. The rest of the mesh config can be changed at runtime and config gets distributed dynamically.

AuthPolicy

Value Description
NONE Do not encrypt Envoy to Envoy traffic.
MUTUALTLS Envoy to Envoy traffic is wrapped into mutual TLS connections.

IngressControllerMode

Value Description
OFF Disables Istio ingress controller.
DEFAULT Istio ingress controller will act on ingress resources that do not contain any annotation or whose annotations match the value specified in the ingressClass parameter described earlier. Use this mode if Istio ingress controller will be the default ingress controller for the entire kubernetes cluster.
STRICT Istio ingress controller will only act on ingress resources whose annotations match the value specified in the ingressClass parameter described earlier. Use this mode if Istio ingress controller will be a secondary ingress controller (e.g., in addition to a cloud-provided ingress controller).

ProxyConfig

ProxyConfig defines variables for individual Envoy instances.

Field Type Description
configPath string Path to the generated configuration file directory. Proxy agent generates the actual configuration and stores it in this directory.
binaryPath string Path to the proxy binary
serviceCluster string

Service cluster defines the name for the serviceCluster that is shared by all Envoy instances. This setting corresponds to --service-cluster flag in Envoy. In a typical Envoy deployment, the service-cluster flag is used to identify the caller, for source-based routing scenarios.

Since Istio does not assign a local service/service version to each Envoy instance, the name is same for all of them. However, the source/caller's identity (e.g., IP address) is encoded in the --service-node flag when launching Envoy. When the RDS service receives API calls from Envoy, it uses the value of the service-node flag to compute routes that are relative to the service instances located at that IP address.

drainDuration Duration The time in seconds that Envoy will drain connections during a hot restart. MUST be >=1s (e.g., 1s/1m/1h)
parentShutdownDuration Duration The time in seconds that Envoy will wait before shutting down the parent process during a hot restart. MUST be >=1s (e.g., 1s/1m/1h). MUST BE greater than drainDuration parameter.
discoveryAddress string Address of the discovery service exposing xDS (e.g. istio-pilot:8080).
discoveryRefreshDelay Duration Polling interval for service discovery (used by EDS, CDS, LDS, but not RDS). (MUST BE >=1ms)
zipkinAddress string Address of the Zipkin service (e.g. zipkin:9411).
connectTimeout Duration Connection timeout used by Envoy for supporting services. (MUST BE >=1ms)
statsdUdpAddress string IP Address and Port of a statsd UDP listener (e.g. 10.75.241.127:9125).
proxyAdminPort int32 Port on which Envoy should listen for administrative commands.
availabilityZone string The availability zone where this Envoy instance is running. When running Envoy as a sidecar in Kubernetes, this flag must be one of the availability zones assigned to a node using failure-domain.beta.kubernetes.io/zone annotation.