OpManager monitors the system resources using SNMP by default. But if needed, you can also add monitors based on CLI, and both these types of monitors will work in tandem. All the Unix Servers templates have the resource monitors preconfigured. All you need to do is to select the CLI monitors and associate them to the required devices.
For monitoring the Unix servers, make sure either Telnet or SSH is enabled on them.
Steps to configure Telnet/SSH Monitoring: