I have been trying to find information and possible issues with running a cluster of dovecot server with different versions without any luck.

We have an existing cluster with dovecot v1.1.10 and tried migrating to a new cluster with dovecot v2.0.12. We ran into some issues when we moved traffic to the new cluster and have been unable to reproduce it in our own testing. We may need to put real usage on the new servers but would like to be able to do this by adding newer servers into the existing cluster.

What are the potential issues with doing this?

Thanks, --Ian

This message and any attachments to it are intended only for the addressee(s) identified above and may contain CONFIDENTIAL information. It is not intended for transmission to, or receipt by, any unauthorized persons. If you are not an intended recipient or an agent responsible for delivering it to an intended recipient, you have received this e-mail in error and any dissemination, distribution, or copying of this message or any attachment to it is strictly prohibited. If you have received this email in error, please (i) do not read it, (ii) reply to the sender that you received the message in error, and (iii) erase or destroy the message from your system.