RabbitMQ amqplib - "Error: Channel closed by server: 406 (PRECONDITION-FAILED) with message "PRECONDITION_FAILED - unknown delivery tag 1"

If you are struggling with the 406 error message which is included in title of this post you may be interested in reading the whole story.

Problem

I was using amqplib for conneting NodeJS based messages processor with RabbitMQ broker. Everything seems to be working fine, but from time to time 406 (PRECONDINTION-FAILED) message shows up in the log:

"Error: Channel closed by server: 406 (PRECONDITION-FAILED) with message "PRECONDITION_FAILED - unknown delivery tag 1"

Solution

Keeping things simple:

• You have to ACK messages in same order as they arrive to your system
• You can't ACK messages on a different channel than that they arrive on

If you break any of these rules you will face 406 (PRECONDITION-FAILED) error message.