Hi Derrence,
HCM does not fully support monitoring HCP using only an IP address.
As per our documentation on the adding sources page:
HCP System to Monitor
The fully-qualified domain name of the HCP system to monitor.
Note: If you don't specify the fully-qualified domain name for your HCP system, HCM may be able to collect data from some signals, but not all.
Hope this helps,
-Jared