The break that is only computed

The startup idea

The problem

A change window is the first time anyone sees what the config actually does.

Who would pay for this?

Primary

Someone about to change a small vendor-style network.

Secondary

A person who will paste configs and confirm the cables.

Early adopter

One device, one show command, labeled computed.

How could it make money?

Possible models. Nothing here is a claim about what Dry Run Lab charges.

• No price. Apache 2.0.
• A buy-me-a-coffee link is the support line.
• The post says free.

What would the MVP look like?

1. A drawn topology.
2. A pasted config.
3. A computed show command.
4. The not-proof line next to the result.

How to validate the idea

• Ask five operators whether they would skip the change window because the sim was green.
• If they would, the label failed.
• Do not compare it with a live device and call a match guaranteed.

How to differentiate

• Nothing is uploaded.
• It never opens a session to the device.
• The result says it is computed.
• Do not become the network vendor.

Product that inspired this idea

Paul's post says Dry Run Lab is a free, open-source network simulator in public beta. Load your real router and switch configs, try the change, and see exactly what breaks before the window. The readme says Apache 2.0. It is a beta, for a small vendor-style network. You draw the devices, paste a config, and confirm the cables it inferred. Show commands are computed on this machine by Batfish. Nothing is uploaded, and it never opens a session to a real device. Results are computed, not proof that the live network, or another software release, will match. It is not affiliated with Cisco. The post says exactly what breaks. The readme says the result is not that. This page did not load a config.

Posted by @pawel7. Watch the original launch. No separate product site is listed unless the post itself is the source.

• network
• simulator

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