Terminology

• 1: Concepts
• 2: Networking
• 3: Observability

1 - Concepts

Application

Is a logical grouping of Workloads defined by the application labels that users apply to an object. In Istio it is defined by the Label App. See Istio Label Requirements.

Application Name

It’s the name of the Application deployed in your environment. This name is provided by the Label App on the Workload.

Istio object/configuration Type

This is the type specified in the Istio Config. This could be any of the following types: Gateway, Virtual Service, DestinationRule, ServiceEntry, Rule, Quota or QuotaSpecBinding.

Istio Sidecar

For more information see the Istio Sidecar definition in Istio Sidecar Documentation.

Label

It’s a user-created tag to identify a set of objects.

An empty label selector (that is, one with zero requirements) selects every object in the collection.

A null label selector (which is only possible for optional selector fields) selects no objects.

For example, Istio uses the Label App & Label Version on a Workload to specify the version and the application.

Label App

This is the ‘app’ label on an object. For more information, see Istio Label Requirements.

Label Version

This is the ‘version’ label on an object. For more information, see Istio Label Requirements.

Namespace

Namespaces are intended for use in environments with many users spread across multiple teams, or projects.

Namespaces are a way to divide cluster resources between multiple users.

Quota

A limited or fixed number or amount of resources.

ReplicaSet

Ensures that a specified number of pod replicas are running at any one time.

Service

A Service is an abstraction which defines a logical set of Pods and a policy by which to access them. A Service is determined by a Label.

Service Entry

For more information see the Service Entry definition in Istio Service Entry Documentation.

Virtual Service

For more information see the Virtual Service definition in Istio VirtualService Documentation.

Workload

For more information see the Istio Workload definition.

2 - Networking

Destination

For more information see the Destination definition in the Istio Glossary.

Destination Rule

For more information see the Istio Destination Rule Documentation.

Endpoint

A communication endpoint is a type of communication network node. It is an interface exposed by a communicating party or by a communication channel.

Error Rate

It’s the percentage of errors in the traffic to a specific object for a Rate Interval.

Gateway

For more information see the Gateway definition in the Istio Gateway Documentation.

Inbound Metrics

Metrics on requests received by a given Workload, Service or Application.

Outbound Metrics

Metrics on requests emitted by a given Workload or Application.

Port

For more information see the Istio Port Documentation.

Rate Interval

It’s an amount of time. By Default in Kiali last 10 minutes.

Rule

It’s an object that manages external access to the services in a cluster, typically HTTP.

Source

For more information see the Source definition in the Istio Glossary.

Subset

For more information see the Istio Subset Documentation.

3 - Observability

Envoy

A proxy that Istio starts for each pod in the service mesh. For more information see the Istio Envoy Documentation.

Envoy Health

A health check performed by Envoy proxies, for inbound and outbound traffic: see membership_healthy and membership_total from Envoy documentation.