A model shutdown occurs if the consumer does not acknowledge the received message in 15 minutes

[Kalhorn]

Rabbit MQ Version: 3.8.16
Erlang Version: 23.3.4
Dot Net Client Version: 5.1.2

Since upgrading to 3.8.16 from 3.8.14 we are seeing that a consumer is being shutdown if processing of the received message takes longer than 15 minutes.

The queue is a Durable, Single Access Consumer queue
I am using the 3-management docker image for this test.

Output from my test, the handler should simply wait for 20 minutes then acknowledge the message

Received Msg : 0, 1 (0)
Waiting for 20 minutes 11/05/2021 14:52:27
[Shutdown Handler] Model shutdown 11/05/2021 15:08:26
[Shutdown Handler] AMQP close-reason, initiated by Peer, code=406, text='PRECONDITION_FAILED - consumer ack timed out on channel 1', classId=0, methodId=0
Wait complete

Same test running against RabbitMQ Version: 3.8.14

Received Msg : 0, 1 (0)
Waiting for 20 minutes 11/05/2021 15:13:34
Wait complete

[michaelklishin]

This is by design: introduced in #2990. See 3.8.15 release notes. The value is configurable.