to check this you have to do the following steps:
-Log in to the SEM, choose Resource management > Device management > Device list.
-Check whether the faulty device is offline in the device list.
-If the faulty device is offline, check whether the network between the device and other servers is normal.
-If the network is normal, log in to the offline device in SSH mode and run the service SEM-Agent restart command to restart the SEM-Agent service.
-Log in to the SEM and check whether the device is online in the device list.
