There are probably multiple ways to do it. I just tested by installing and enabling OpenSSH on a Windows Server 2019 system. I ran a discovery against the OS IP address using admin credentials. It returned a successful discovery with status "monitored". You can probably use SNMP as well.
Hi,  I recently successfully migrated from OpenManage Essentials to OpenManage Enterprise and have discovered all the servers via their iDracs. However, I'm unsure how OpenManage Administrator ver 9 (OMSA), that is running on each server can integrate with Enterprise? I can see how OpenManage integrated into Essentials, so apologies if I'm missing the obvious. Does it integrate via being able to discover via SNMP and using the servers community name, as specified on its SNMP service? (as this sadly fails on Enterprise but works on Essentials and the Dell EMC Troubleshooting Tool can also discover the server via SNMP).  I ask because some log oversize alerts from the OpenManage Administrator v9 (OMSA) do not appear as alerts in the Dracs or within OpenManage Enterprise 3.2.1.  Kind regards Dell OpenManage Enterprise = Version 3.2.1 (Build 29)Dell EMC OpenManage Systems Management Software (64-Bit) Version 9.1.0. **Or is it true that Enterprise can not communicate with Administrator?   [URL]#M2274  
How to integrate Dell OpenManage Administrator into Dell OpenManage Enterprise