Does the
leader just wait for the followers in the ISR to consume?

That's right. Until that is done, the producer does not get an ack back. It
has an option of retrying if the previous request times out or fails.

A separate question, can the request.required.acks be set to a higher
positive integer, say "2", to indicate that 2 of say 3 replicas have acked?

Yes that's possible.

On Oct 5, 2013 10:18 AM, "Jason Rosenberg" <[EMAIL PROTECTED]> wrote:
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