Knative Serving
Knative Serving builds on Kubernetes and Istio to support deploying and serving
of serverless applications and functions. Serving is easy to get started with
and scales to support advanced scenarios.
The Knative Serving project provides middleware primitives that enable:
- Rapid deployment of serverless containers
- Automatic scaling up and down to zero
- Routing and network programming for Istio components
- Point-in-time snapshots of deployed code and configurations
Serving resources
Knative Serving defines a set of objects as Kubernetes
Custom Resource Definitions (CRDs). These objects are used to define and control
how your serverless workload behaves on the cluster:
- Service:
The
service.serving.knative.dev
resource automatically manages the whole
lifecycle of your workload. It controls the creation of other
objects to ensure that your app has a route, a configuration, and a new revision
for each update of the service. Service can be defined to always route traffic to the
latest revision or to a pinned revision.
- Route:
The
route.serving.knative.dev
resource maps a network endpoint to a one or
more revisions. You can manage the traffic in several ways, including fractional
traffic and named routes.
- Configuration:
The
configuration.serving.knative.dev
resource maintains
the desired state for your deployment. It provides a clean separation between
code and configuration and follows the Twelve-Factor App methodology. Modifying a configuration
creates a new revision.
- Revision:
The
revision.serving.knative.dev
resource is a point-in-time snapshot
of the code and configuration for each modification made to the workload. Revisions
are immutable objects and can be retained for as long as useful.
Getting Started
To get started with Serving, check out one of the hello world sample projects.
These projects use the Service
resource, which manages all of the details for you.
With the Service
resource, a deployed service will automatically have a matching route
and configuration created. Each time the Service
is updated, a new revision is
created.
For more information on the resources and their interactions, see the
Resource Types Overview
in the Knative Serving repository.
More samples and demos
Setting up Logging and Metrics
Debugging Knative Serving issues
Configuration and Networking
Known Issues
See the Knative Serving Issues page for a full list of
known issues.
Except as otherwise noted, the content of this page is licensed under the
Creative Commons Attribution 4.0 License,
and code samples are licensed under the
Apache 2.0 License.