This code in qemu_driver.c doesn't look right to me. I think the second should be a call to brSetEnableSTP? Rich. if (network->def->forwardDelay && (err = brSetForwardDelay(driver->brctl, network->bridge, network->def->forwardDelay))) { qemudReportError(conn, NULL, NULL, VIR_ERR_INTERNAL_ERROR, "failed to set bridge forward delay to %d\n", network->def->forwardDelay); goto err_delbr; } if ((err = brSetForwardDelay(driver->brctl, network->bridge, network->def->disableSTP ? 0 : 1))) { qemudReportError(conn, NULL, NULL, VIR_ERR_INTERNAL_ERROR, "failed to set bridge STP to %s\n", network->def->disableSTP ? "off" : "on"); goto err_delbr; } -- Emerging Technologies, Red Hat - http://et.redhat.com/~rjones/ Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 03798903