Random io.netty.channel.AbstractChannel$AnnotatedConnectException on GitHub Actions

[Roman Pierson]

Hi

Quite aware this is not a direct Vertx related question but maybe some of you might have experienced the same and in the best case would have an idea what's going on.

Basically recently moved CI from Travis ti GH Actions and also implemented component tests that start verticles on Vertx and run client requests against it.

https://github.com/romanpierson/vertx-web-accesslog/blob/master/src/test/java/com/mdac/vertx/web/accesslogger/AcessLogServerTest.java

Those tests run always successfully on my local java 11 os x environment.

When it runs on GH Actions (Having CI for various Java versions and one for Sonar) I started to get failures for some of them, mostly failing one or two of the test methods with this

io.netty.channel.AbstractChannel$AnnotatedConnectException

Caused by: java.net.ConnectException at Net.java:-2

Started then to play around with java versions (and distributions) and for now only running CI with java 8 and Sonar with Java 17 seems to work (and java 11 seems to be reliable failing), but that might be pretty coincidence I fear.

However they are never failing on my local environment.

Is there anything wrong/brittle the way the tests are written that might cause the issue in those CI environments? I assume vertx core project also uses GH Actions now and kind of similar tests?