Component Introspection

Istio components are built with a flexible introspection framework which makes it easy to inspect and manipulate the internal state of a running component. Components open a port which can be used from a web browser to get an interactive view into the state of the component, or via REST for access and control from external tools.

Mixer, Pilot, and Galley all implement the ControlZ functionality. When these components start, a message is logged indicating the IP address and port to connect to in order to interact with ControlZ.

2018-07-26T23:28:48.889370Z     info    ControlZ available at 100.76.122.230:9876

Here's sample of the ControlZ interface:

ControlZ User Interface
ControlZ User Interface

The --ctrlz_port and --ctrlz_address command-line options can be given when starting a component to control the specific address and port where ControlZ should be exposed.

To access the ControlZ page of deployed components (i.e. Mixer, Galley, Pilot), you can port-forward their ControlZ endpoints locally and connect through your local browser:

$ kubectl port-forward -n istio-system <podname> 9876:9876

This will redirect the component's ControlZ page to http://localhost:9876 for remote access.