network-change-verification

name	network-change-verification
description	Pre/post verification checklist for network and routing changes. Use before and after any DNS, routing, tunnel, or proxy change, when exposing a new service externally, or when troubleshooting connectivity issues.
license	MIT

Network Change Verification

Pre/post verification checklist for network and routing changes.

When to Use

Verifying connectivity around a change — the before/after probes for a DNS, route, tunnel, or proxy edit. Its sibling network-documentation owns the record of the resulting topology: verify the change works here, then update the source-of-truth there. Verification is the test; documentation is the artifact.

Before Change

1. Source Check: Verify external DNS/Domain points to the correct IP.
2. Path Check: Verify tunnels (WireGuard, etc.) are active.
3. Destination Check: Run curl or nc on the target to confirm the service is listening.

After Change

1. Summarize flow: Document the new traffic path (e.g., User → HTTPS (443) → Traefik → Tunnel → Service (8080)).
2. Verify end-to-end: Confirm the full path works from the external entry point.
3. Update docs: Ask the user to verify the documentation update.

Completion

• Pre-change baseline captured
• Post-change end-to-end connectivity verified
• Traffic path documented and docs updated

Anti-Patterns

• Skipping pre-change baseline — can't tell if the change broke something or it was already broken
• Verifying only internal hops — must test from the external entry point
• Forgetting doc update — next person won't know the new path