I couldn't find this answer in the archives. I suspect that I am missing a
step somewhere so I'd appreciate any clarification someone could offer:

On a broadcast network, Router A is the DR, Router B is the BDR, and Router C
and D are DRother routers. Router A goes offline, but it is still within the
DeadInterval so the other routers are not aware of this yet. Router C floods
an update packet to AllDrouters. Router B receives this packet but does not
acknowledge it because it is the BDR and it wasn't flooded out the receiving
interface (13.5) At this point Router B also adds the LSA to the
retransmission list for router A and D (but not neighbor C since it sourced
the packet) but it does not flood the packet onto the interface since it is
the BDR (13.3). Now, since Router A is down and D will not receive the packet
or acknowledge it Router B will end up sending a retransmission to Router D as
a unicast with the LSA. However, the problem I see is that at no point will
Router B acknowledge the receipt of the LSA to Router C, so Router C will end
up retransmitting the LSA to Router B. Am I missing something somewhere?

Thanks.

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