[rabbitmq-discuss] publisher confirm ack nack ordering

[Matthias Radestock]

Tobias,

On 04/07/13 09:04, Tobias Gutzmann wrote:
> Assuming that a few messages succeed in order, I sometimes see the ACKs
> like this (RabbitMQ 3.1.1):
>
> ACK(5, true)
> ACK(1, false) -- surely sent first by the broker, but lagged a bit
> longer on the wire

That should not happen. Are you sure the messages were a) sent on the 
same channel, and b) not re-ordered in the application code?

Can you capture a protocol trace (e.g. using 
http://www.rabbitmq.com/api-guide.html#tracer) showing the above?

> Now the problem, which I haven't observed as it should be extremely rare
> but which still is possible:
>
> ACK (5, true)
> NACK (1, false) -- sent first by broker but received last.

That shouldn't happen either.

Regards,

Matthias.