It appears that interfaces participate in STP's forwarding delay even when STP is disabled for a given bridge. I can remedy by setting the FD to 0 for each new bridge, but I'm wondering if this is by design or oversight. [root@ ~]# brctl show bridge name bridge id STP enabled interfaces br0.690 8000.00065b8bce3e no eth1.690 eth0.690 [root@ ~]# brctl showstp br0.690 br0.690 bridge id 8000.00065b8bce3e designated root 8000.00065b8bce3e root port 0 path cost 0 max age 19.99 bridge max age 19.99 hello time 1.99 bridge hello time 1.99 forward delay 14.99 bridge forward delay 14.99 ageing time 299.95 hello timer 1.09 tcn timer 0.00 topology change timer 0.00 gc timer 0.00 flags eth1.690 (2) port id 8002 state forwarding designated root 8000.00065b8bce3e path cost 100 designated bridge 8000.00065b8bce3e message age timer 0.00 designated port 8002 forward delay timer 0.00 designated cost 0 hold timer 0.09 flags eth0.690 (1) port id 8001 state forwarding designated root 8000.00065b8bce3e path cost 19 designated bridge 8000.00065b8bce3e message age timer 0.00 designated port 8001 forward delay timer 0.00 designated cost 0 hold timer 0.09 flags !! when i restart networking: [root at vlan-fw-02 ~]# tail /var/log/messages -n50 | grep 690 Mar 16 08:01:33 vlan-fw-02 kernel: br0.690: port 2(eth1.690) entering disabled state Mar 16 08:01:33 vlan-fw-02 kernel: br0.690: port 1(eth0.690) entering disabled state Mar 16 08:01:33 vlan-fw-02 kernel: device eth0.690 left promiscuous mode Mar 16 08:01:33 vlan-fw-02 kernel: br0.690: port 1(eth0.690) entering disabled state Mar 16 08:01:34 vlan-fw-02 kernel: device eth1.690 left promiscuous mode Mar 16 08:01:34 vlan-fw-02 kernel: br0.690: port 2(eth1.690) entering disabled state Mar 16 08:01:35 vlan-fw-02 kernel: eth0.690: dev_set_promiscuity(master, -1) Mar 16 08:01:36 vlan-fw-02 kernel: eth1.690: dev_set_promiscuity(master, -1) Mar 16 08:01:36 vlan-fw-02 kernel: eth0.690: dev_set_promiscuity(master, 1) Mar 16 08:01:36 vlan-fw-02 kernel: device eth0.690 entered promiscuous mode Mar 16 08:01:36 vlan-fw-02 kernel: eth1.690: dev_set_promiscuity(master, 1) Mar 16 08:01:36 vlan-fw-02 kernel: device eth1.690 entered promiscuous mode Mar 16 08:01:37 vlan-fw-02 kernel: br0.690: port 2(eth1.690) entering learning state Mar 16 08:01:37 vlan-fw-02 kernel: br0.690: port 1(eth0.690) entering learning state Mar 16 08:01:52 vlan-fw-02 kernel: br0.690: topology change detected, propagating Mar 16 08:01:52 vlan-fw-02 kernel: br0.690: port 2(eth1.690) entering forwarding state Mar 16 08:01:52 vlan-fw-02 kernel: br0.690: topology change detected, propagating Mar 16 08:01:52 vlan-fw-02 kernel: br0.690: port 1(eth0.690) entering forwarding state