[fargate] [request]: document HOSTNAME environment variable behavior

[terrbear]

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It seems in the last few days, Fargate behavior changed, to where you cannot write the HOSTNAME environment variable through a task definition. Instead, it's overridden to the actual host's hostname.

For anyone who relied on that variable, it was a breaking change :)

I didn't see it in the environment variables available docs, so that should probably be called out.

Which service(s) is this request for? Only tested this on Fargate

Are you currently working around this issue? Changed envvar name.

[gbooth27]

we are running into this too

[monim67]

Is the environment variables documented? I can only find this gist which tells me AWS fargate overrides my HOSTNAME variable breaking my nextjs application.

[lifeofguenter]

Is the environment variables documented? I can only find this gist which tells me AWS fargate overrides my HOSTNAME variable breaking my nextjs application.

I think there are much better variables that should be used instead of HOSTNAME, for example LISTEN_HOST or even LISTEN_INTERFACE.