content/en/docs/ops/diagnostic-tools/controlz/index.md
Istiod is built with a flexible introspection framework, called ControlZ, which makes it easy to inspect and manipulate the internal state of an istiod instance. Istiod opens a port which can be used from a web browser to get an interactive view into its state, or via REST for access and control from external tools.
When Istiod starts, a message is logged indicating the IP address and port to connect to in order to interact with ControlZ.
{{< text plain >}} 2020-08-04T23:28:48.889370Z info ControlZ available at 100.76.122.230:9876 {{< /text >}}
Here's sample of the ControlZ interface:
{{< image width="90%" link="./ctrlz.png" caption="ControlZ User Interface" >}}
To access the ControlZ page of istiod, you can port-forward its ControlZ endpoint locally and connect through your local browser:
{{< text bash >}} $ istioctl dashboard controlz deployment/istiod.istio-system {{< /text >}}
This will redirect the component's ControlZ page to http://localhost:9876 for remote access.