[rabbitmq-discuss] Shovel stops receiving acks from cluster

Tue Aug 14 13:27:26 BST 2012

Hello.

I have a cluster consisting of two nodes, and brokers shoveling messages to the cluster using the
shovel plugin. When testing failover with the shovel plugins (by stopping the RabbitMQ nodes) I often
see that when starting a node after stopping it causes the shovel plugin to stop receiving acks for
messages. I have prefetch_count set to 1000 in the shovel config, and I see that "unacked" in the
management interface for the queue rises to 1000 and sits there, with "ready" steadily increasing.
The connection seems to be alive as I can see (via tcpdump) that there are heartbeats being sent.
All RabbitMQ servers are 2.8.5 on Erlang R14A. This only seems to happen with setting ack_mode
set to on_confirm. The queues on the cluster are mirrored using x-ha-policy: all.

Any help or ideas much appreciated.

Jon