There are two ways to add network devices.
The first option is simply navigating to Device > Network Devices and clicking on the "+" icon, filling out the necessary details such as Probe, Hostname or IP, SNMP credential, Monitoring Template, Tags (if required) and then saving it.
The second option is to navigate to Settings, choose Monitoring, select Probes, click on the Edit option, navigate to the network device, select on the "+" icon, fill out the required information such as Probe, Hostname or IP, SNMP credential, Monitoring Template, Tags (if required), and then save the changes.
Note: Prior to adding a network device, it is necessary to set up SNMP credentials. To configure an SNMP credential, you can refer to the instructions provided in the link below.
Steps to add SNMP Credentials