> promiscuous mode is tracked in the kernel with a counter, the kernel > won't change the actual hardware until the counter goes to zero. This is > why running something like tcpdump which changes interface to promiscuous mode > will have no effect on the bridge. How did you > force the interface out of non-promiscious mode? You may not changed anything. > I simply did "ifconfig eth0 -promisc" and "ifconfig tap0 -promisc". "ifconfig" then no longer indicates that the interfaces are in promiscuous mode. Are you saying that the output of ifconfig is not reliable and that the interfaces may in fact still be in promiscuous mode? This would make sense, but then how come the performance seems to be affected by the change? > Also promiscuous on tap means nothing really since there is no hardware > filtering. OK. I thought there might have been some software simulation of the promiscuous mode. Thanks, Lionel.