[jboss-jira] [JBoss JIRA] Resolved: (JGRP-968) UNICAST: loss of first msg after asymmetric close causes all further messages to be lost

UNICAST: loss of first msg after asymmetric close causes all further messages to be lost ---------------------------------------------------------------------------------------- Key: JGRP-968 URL: https://jira.jboss.org/jira/browse/JGRP-968 Project: JGroups Issue Type: Bug Reporter: Bela Ban Assignee: Bela Ban Fix For: 2.6.10.merge, 2.8 This is scenario #6 in UNICAST.new.txt #4 A closes the connection unilaterally (B keeps it open), then reopens it and sends a message: - A removes the entry for B from its connection table, cancelling all pending retransmissions - (Assuming that B's entry.recv_win for A is at #25) - A creates a new entry for B in its connection table - Entry.send-conn-id is set and sent with the message - Entry.seqno now is 1 - B receives the message with a new conn-id - B does have an entry for A, but entry.recv-conn-id doesn't match msg.conn-id - B creates a new entry.recv_win, sets it to msg.seqno - B sets entry.recv-conn-id to msg.conn-id #6 Same as #4, but after re-establishing the connection to B, A loses the first message (first part of #4) - A creates a new sender window for B - A sends #1(conn-id=322649) #2(conn-id=0) #3(conn-id=0), but loses #1 - B receives #2 first. It thinks this is part of a regular connection, so it doesn't trash its receiver window - B expects a seqno higher than #2 (from the prev conversation with A), and discards #2, but *acks* it nevertheless - A removes #2 from its sender window - B now finally receives #1, and creates a new receiver window for A at #1 - A retransmits #3 - B stores #3 but doesn't deliver it because it hasn't received #2 yet - However, B will *never* receive #2 from A because that seqno has been removed from A's sender window !