So here is the brunt of it: Two Quad Core xServes, identical in every way. Two Foundry switches identical in every way with LACP support. I ran a network cable from each ethernet port, one to one switch, one to the other for HA. Same for the other xserve. I turn on ethernet bonding on one, working fine everything connects up. I turn it on on the other one, nothing connects, gives "wrong group" error under advanced. What is going on here, if I flip flop them, then the other one works. But only one will work at a time. How is a software ethernet bond messing with the other server?????? I tried the dinky stuff like MAC address being the same, bad cable etc. The switch is configured correctly, I have many a dell server running the exact same way as this. I know I have to be overlooking something stupid I'm guessing but this is driving me crazy, any help would be appreciated.