Brian, There is no way that at the time block is propagate up from FLUSH to Channel that we know which node is a state provider. The only parameter with BLOCK event that we could possibly send up the stack is the identity of the node that invoked FLUSH. In the case of state transfer that node is state requester. So as you suggest we'll have to do some additional work once getState reaches state provider. The call for unblock, as Bela explained today privately, is: Pull model (Channel.receive()): Channel.blockOk() Push model (Receiver.block()): Returning from block() is an ack, so Channel.blockOk() does *not* need to be called ! View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3971353#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...