966: add vm auto-discovery note; virtual-machine-auto-discovery

Author: jamesdanielwhitford

docs/auto-discovery/virtual-machine-auto-discovery.mdx

@@ -61,6 +61,10 @@ From the Device42 main menu, under **Discovery > Hypervisors/\*nix/Windows**, ad
 
 **Discovery Target(s):**  This is the FQDN or IP of the vCenter server or the ESX server. If using FQDN, set up DNS resolution in the Device42 VM console first.
 
+:::note
+You need to add each vCenter server you wish to discover. Device42 does not automatically find or crawl additional vCenter servers linked to your first one.
+:::
+
 **Port:** This is 443 by default. Only change if you have changed it.
 
 **Enable Resource Utilization Tracking for Device(s):** This option enables the periodic collection and examination of server resource usage metrics. See [Resource Utilization](/auto-discovery/resource-utilization-overview/) for more information.
@@ -202,4 +206,4 @@ Newly created jobs will not run on the first day they are created to prevent an
 
 ## Under the Hood
 
-Device42 uses VMware APIs and the open-source library [pyvmomi](https://github.com/vmware/pyvmomi).
+Device42 uses VMware APIs and the open-source library [pyvmomi](https://github.com/vmware/pyvmomi).