bridge name     bridge id               STP enabled     interfaces
xenbr0          8000.feffffffffff       no              peth0
                                                        vif0.0
xenbr1          8000.000000000000       no               can't get port info: Function not implemented
xenbr2          8000.000000000000       no               can't get port info: Function not implemented
xenbr3          8000.000000000000       no               can't get port info: Function not implemented