PHP unit tests against scality server are failing in CI

[phil-davis]

Steps to reproduce

https://drone.owncloud.com/owncloud/core/40378/26/11

[{"reqId":"WetWABWgVflDIvxQK3oy","level":3,"time":"088900","remoteAddr":"","user":"--","app":"no app in context","method":"--","url":"--","message":
"Exception: {\"Exception\":\"Aws\\\\S3\\\\Exception\\\\S3Exception\",\"Message\":\"Error executing \\\"ListBuckets\\\" on \\\"http:\\\/\\\/scality:8000\\\/\\\"; AWS HTTP error: cURL error 6: getaddrinfo() thread failed to start 
(see https:\\\/\\\/curl.haxx.se\\\/libcurl\\\/c\\\/libcurl-errors.html) for http:\\\/\\\/scality:8000\\\/\",\"Code\":0,\"
Trace\":\"#0 \\\/drone\\\/src\\\/apps\\\/files_primary_s3\\\/vendor\\\/aws\\\/aws-sdk-php\\\/src\\\/WrappedHttpHandler.php(97): Aws\\\\WrappedHttpHandler->parseError()
...

After more than 10,000 unit tests, it starts failing. Some S3 problem with the scality server running at http://scality:8000

Happens in all PRs these days. Needs investigation.

Today's example PR #41423

Expected behaviour

PHP unit tests pass

Actual behaviour

Some tests fail

Server configuration

CI on master branch

[DeepDiver1975]

Looks like a DNS resolution issue.
Drone I restart? Docker restart?

[phil-davis]

I have restarted, it happens the same with every PR.
More than 10k unit tests pass, then it starts failing. Maybe those first 10k unit tests do not depend on the storage.

[phil-davis]

Same problem today, for example in PR #41423
https://drone.owncloud.com/owncloud/core/40382/26/11

[phil-davis]

owncloud/files_primary_s3#693 (comment) also has a problem with the unit tests, but it happens earlier with "Too many open files" messages.