What does "dfw [warn] Instance reached connections hard limit of 25" mean?

I saw this in my logs and don’t know what it means:

2021-07-16T13:20:56.614499379Z proxy[6e3ab6c3] dfw [warn] Instance reached connections hard limit of 25

Should I be concerned? What can I do about this?

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This means the app has as many connections to a particular VM as its allowed. When this happens, we route requests to the next closest VM with capacity.

There are settings in fly.toml that control this, you’ll see a soft limit (which controls scaling) and a hard limit, which is what you hit. You can likely set that very high if your app is lightweight. Like 100-200.

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Sweet :+1:

What could happen if I set it to something too high, like 1000?

Worst case is we overload your app process, which will make the app unresponsive for people.

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