Naming of discovered devices can be controlled via the Advanced section of the Discovery Profile:
TechDocs : DX NetOps Performance Management 22.2 : Manage Discovery Profiles
(see step 6)
- In the Naming Order and Reconciliation Options section, define the priority NetOps Portal uses to name the discovered devices. NetOps Portal names the device items that the discovery profile creates using the highest available naming convention. To change the priority, select a name from the list and then use the Move Up or Move Down arrows. If a higher priority attribute is unavailable for the device, NetOps Portal uses the next highest priority attribute. For virtual machines, NetOps Portal ignores the naming order and uses the names from vCenter.
If the name is found in either the sysName.0 or DNS for the entry, moving whichever one holds the name to the top of the order for naming will apply the name to the device.
If the DNS hostname has been updated and is what is already being used it can take up to 48 hours to reflect the change:
TechDocs : DX NetOps Performance Management 22.2 : Manage Hostname Changes