On Monday, 09/21/2009 at 09:29 EDT, "Moore, Terry A." <[email protected]> wrote: > Turned out to be a wrong duplex setting on the switch in that remote office. > Apparently VM was more susceptible to it than OS/390, but we expect that the > OS/390 applications were running very slowly even though they weren't dropping.
The only thing that happens when you incorrectly set half-duplex on a switch port is that many of the packets are dropped. (The port will not send and receive at the same time.) Those dropped packets will eventually result in retransmissions by the affected hosts. Best case is that throughput is cut in half. Depending on timing, the worst case is that the session drops. It would still be edifying to learn if it is VM or the emulator that is terminating the connection. Alan Altmark z/VM Development IBM Endicott
