S2S reconnects cause MUC issues in cluster
Scenario: have an Openfire domain that is a cluster (at least two nodes). Have another Openfire domain (needs not be a cluster).
On the clustered domain, create a chatroom.
On the other domain, create a user, have that user join the chatroom.
Now, on the admin console of the other domain, close the S2S session(s) to the clustered domain.
Then, send a message to the chatroom from the user on the remote domain. This will cause S2S to be re-established.
Sometimes - I believe when the S2S session gets re-established to another node than the one previously connected to), the following is logged on one of the nodes on the clustered domain: