You would install the Endpoint Operations (EpOps) agent inside this Linux instance and connect it back to vROps.
If you are looking for monitoring of the physical server itself for things like Chassis / Blade status, thermal characteristics, power Consumption, hardware alerts, etc -- Blue Medora has published a number of vROps Management Packs focused on surfacing that kind of data within vROps for Cisco UCS, HPE Servers, Dell Servers, and others. You can find those MPs in the VMware Solution Exchange here: