Github user markap14 commented on the issue:
https://github.com/apache/nifi/pull/3010
@jtstorck I did just run into an issue that we will need to address. If we
decommission 2 nodes at the same time (say Node 2 and Node 3) then we can end
up in a state where Node 2 is trying to send to Node 3 (or vice versa) but the
node is not connected. As a result, it ends up leaving the data in the queue.---
