Hello, I am experiencing what may be a unique problem with operating the bridge. My hardware is custom Freescale MPC875 processor based with one ethernet (eth0) and one hdlc (hdlc0) WAN port and I am connecting two of these boards together using the WAN ports over a long distance - essentially two bridges in series. They are running Linux 2.6.15 with bridging enabled in the kernel configuration. When I first power up both boards the bridge comes up fine and the two outside LANs are connected as if it were one LAN with a smart long cable in between. brctl works to set it up and the "showmacs" properly shows all of the MACs on each end. The problem occurs If I disconnect the ethernet cable directly from the bridge at either end. The console on the disconnected units says "br0: port 2(eth0) entering disabled state". When I reconnect the cable it shows "br0: port 2(eth0) entering learning state" plus messages about network topology change detected. That LAN end no longer has a link to the other end, yet at the console of the unit disconnected and reconnected I can ping in either direction to any device in both LAN segments. Time makes no difference, but if I issue the command "ifconfig eth0 down" and then back "up" the link is almost immediately restored. This works either while the cable is disconnected or after it is reconnected. I compared the effect of a cable disconnect with a standard PC running Linux and it seems to be identical, that is, ifconfig shows the port as up even when the cable is disconnected on both. I tried having STP enabled or disabled, and adding the ports into br0 in the opposite order with no difference either. Any ideas on why the bridge does not automatically restore? and especially on how I can make it automatically restore itself? Thank you for your kind attention. Mike Boutte
