> For the complete documentation index, see [llms.txt](https://docs.vex-nx.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.vex-nx.com/labs/lab-preflight-and-black-box.md).

# Lab Preflight and Black Box

![Lab preflight report](https://1807546539-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FhgHCHWL3861o2DBW53aA%2Fuploads%2Fju3StjMquQtjRTPnfDB6%2Fve20261112v5-preflight-report.png?alt=media)

## Goal

Run Smart Lab Preflight before Start, and record Network Black Box evidence during incidents or exams.

## Lab Preflight

### Open it

In an open lab: workspace **More** menu -> **Preflight check**. Start-all can also run server preflight and block when issues are fatal.

### What it checks

Images, templates, capacity, and lab lock state (plus related warnings). The report lists:

| Bucket       | Meaning                 |
| ------------ | ----------------------- |
| **Blocking** | Must fix before Start   |
| **Warnings** | Can proceed, but review |
| **Passed**   | Clear                   |

### Recipe

1. Open the lab in Operate (or Design)
2. More -> **Preflight check**
3. Fix blocking items (missing images, capacity, locks)
4. Re-run, then **Start all** when `can start`

## Network Black Box

### Open it

Lab **More** menu -> **Black Box**.

### What you get

| Action                     | Use it for                               |
| -------------------------- | ---------------------------------------- |
| **Start / Stop recording** | Session evidence timeline                |
| **Add note**               | Manual incident markers                  |
| **Event list**             | Recorded events for the lab              |
| **Capture references**     | Links only when a real capture id exists |

Use Black Box when teaching troubleshooting or collecting evidence for a failed Validate / capture session - not as a full packet store.

## Related

* [Packet capture](/labs/packet-capture.md)
* Visualize, Present, and Preview
* Classroom for instructors
* [Features](/getting-started/features.md)


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