First things first... Can you confirm that those are still the values in > place? > > cat /proc/sys/net/ipv4/conf/eth0/arp_filter > cat /proc/sys/net/ipv4/conf/eth0/arp_ignore > cat /proc/sys/net/ipv4/conf/eth1/arp_filter > cat /proc/sys/net/ipv4/conf/eth1/arp_ignore > cat /proc/sys/net/ipv4/conf/all/arp_filter Obviously when we ifdown eth1 the eth1 statements above are 0. Right now eth1 is up with a sysctl -p and all set to 1. Thanks, Gavin.