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Http get lifecycle hook

As explained in Kubernetes in Action, Second Edition

An HTTP GET lifecycle hook sends an HTTP GET request to a specified host, port, and path at a configured container lifecycle event.

An HTTP GET lifecycle hook sends a request to a configured host, port, and path when a container starts. It can initialize or warm up an application without changing its code or container image. section 6.3.1

Warm up a web server

Configure the hook under the container’s post-start lifecycle event: httpGet: host: myservice.example.com, port: 80, path: /container-started. The request can notify or prepare the application as it starts. section 6.3.1

Lifecycle hooks apply only to regular containers, not init containers, and unlike probes they do not support tcpSocket handlers.

How Kubernetes in Action, Second Edition covers it

How deep it goes
Defines host, port, and path configuration, but stops short of describing HTTP response handling or request internals.
Examples
Demonstrates a web-server warm-up request to /container-started on myservice.example.com:80.
What it assumes
Assumes basic container lifecycle configuration while teaching the hook’s purpose and request fields directly.
What you can do after
Operate/configure a Pod manifest with an HTTP GET post-start request targeting a chosen application endpoint.
How it connects
Connects post-start lifecycle hooks with container lifecycle, initialization, warm-up procedures, probes, and init containers.
Cover of Kubernetes in Action, Second Edition
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Related concepts

This explainer was generated by Manning's knowledge graph from the text of Kubernetes in Action, Second Edition. The section links point to the parts of the book it draws on.