Hi, I checkout ovirt-engine's code with branch 4.2; When execute Host's Management --> Active command, ovirt engine just set vds's status to "Unassigned" but how the vds's status changed to "UP" in ovirt-engine? The code in ActiveVdsCommand.executeCommand() as follows: protected void executeCommand() { final VDS vds = getVds(); try (EngineLock monitoringLock = acquireMonitorLock("Activate host")) { executionHandler.updateSpecificActionJobCompleted(vds.getId(), ActionType.MaintenanceVds, false); setSucceeded(setVdsStatus(VDSStatus.Unassigned).getSucceeded()); if (getSucceeded()) { TransactionSupport.executeInNewTransaction(() -> { // set network to operational / non-operational List<Network> networks = networkDao.getAllForCluster(vds.getClusterId()); networkClusterHelper.setStatus(vds.getClusterId(), networks); return null; }); // Start glusterd service on the node, which would haven been stopped due to maintenance if (vds.getClusterSupportsGlusterService()) { runVdsCommand(VDSCommandType.ManageGlusterService, new GlusterServiceVDSParameters(vds.getId(), Arrays.asList("glusterd"), "restart")); // starting vdo service GlusterStatus isRunning = glusterUtil.isVDORunning(vds.getId()); switch (isRunning) { case DOWN: log.info("VDO service is down in host : '{}' with id '{}', starting VDO service", vds.getHostName(), vds.getId()); startVDOService(vds); break; case UP: log.info("VDO service is up in host : '{}' with id '{}', skipping starting of VDO service", vds.getHostName(), vds.getId()); break; case UNKNOWN: log.info("VDO service is not installed host : '{}' with id '{}', ignoring to start VDO service", vds.getHostName(), vds.getId()); break; } } } } } Your Sincerely Mark Lee