[colmmacc]

Full disclosure: I'm an engineer at AWS and I work on NAT Gateway :)

Thanks for the pointer to urllib3 - we'll take a look at it and see if there's anything we can do about the behavior. One of the challenges with sending "FIN" on timeout is, as you write ... it closes the connections cleanly.

Some TCP based protocols (Including even HTTP in some modes) use a successful connection close to indicate that an object has been transferred fully; so what we've seen is that a network connection may stall (internet packet loss for example) ... then the connection eventually times out ... and the "FIN" falsely conveys that the entire object has been transferred. The end result is a truncated object, which is no good either.

[narsil]

Thanks for the explanation colmmacc! I agree with the challenge you described, and am not sure what the best approach would be. Perhaps a configurable timeout such as ELBs have?