Test hook: Running multiple MinIO servers on the same host seems to cause problems

[alanking]

The test hook starts two MinIO servers on the same host, running in different S3 regions with different ports. This has worked fine up until I tried to run tests for 4-2-stable in Ubuntu 18.04 in the testing environment. I started getting strange errors in the MinIO logs and the tests keep getting stuck and timing out when doing simple things like deleting buckets.

I would suggest that we make the S3 region an option which can be passed via the test hook. Then, the region can be set by this option when starting the MinIO server and running the tests. As there is no way (that I know of) to pass it as an option to the unittest framework, we have separate test suites for different regions right now. If the region is passed as an option or derived from the environment, then we can run any test using any S3 region.

[korydraughn]

And 4.3 doesn't have this problem?

[alanking]

I did not observe this problem outside of 4-2-stable, but it may be a problem with older platforms (e.g. ubuntu 18.04) which are still supported in 4.3.x. Haven't taken the time to find conclusive evidence for that. Either way, I feel that this suggested change would be an improvement to include in the main branch/4.3 series because it allows for testing more combinations of configurations and regions.

[korydraughn]

I'm all for improving support for testing. It may not be an issue right now, but it likely will be in the future. So, let's expose the option as you've suggested.

[JustinKyleJames]

I believe this might be the same issue as #2112. If so a workaround has been implemented in 4-2-stable.