# WHATPORT(9876)

## NAME

port 9876 — Karma test runner; sd (Session Director) — IANA says Session Director, but on a developer's machine this is almost always the Karma browser test runner.

Protocol: TCP  
IANA registry

## DESCRIPTION

The registration is `sd`, "Session Director", from Van Jacobson's MBone-era session-announcement work, which you will effectively never meet today. What you will meet is Karma: its default `port` config value is 9876, and it runs a web server that browsers connect to in order to execute a project's unit tests. Karma was deprecated by its maintainers in favour of Web Test Runner, Jest, and Vitest, but it is still present in many Angular and older JavaScript projects, so a listener on 9876 usually means a test run in progress or a CI container that did not shut down.

## EXPOSURE

**Do not expose.** Karma exists to load arbitrary project JavaScript into a connected browser. Exposing it hands strangers a code-execution surface in whatever browser reaches it; keep it bound to localhost.

## CHECK

```sh
curl -sI http://localhost:9876/
```

## SEE ALSO

- docs — [Karma configuration file reference (port default 9876)](https://karma-runner.github.io/latest/config/configuration-file.html) (karma-runner.github.io)
- source — [Karma source repository (deprecated)](https://github.com/karma-runner/karma) (github.com)
- iana — [IANA Service Name and Transport Protocol Port Number Registry](https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml) (iana.org)

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HTML: <https://whatport.net/9876/> · JSON: <https://whatport.net/9876.json> · full dataset: <https://whatport.net/ports.json>