OpenAPI Query Fails to Return Data

Products

• Network Observability
• CA Performance Management

Issue/Introduction

Data is available and visible in graphs, but OpenAPI queries return no data 

Environment

Performance Management - All Supported versions

Cause

The API query fails when attempting to identify a device by its hostname if the hostname field is not populated on the device administration page. For Data Aggregator device, hostnames are determined via DNS; if DNS resolution fails or a discovery has not been performed since the hostname became available, the field remains empty

Resolution

The following article outlines additional information on populating the hostname:
Hostname blank on several devices.

Additional Information

WORKAROUND

Use Name, DisplayName or another identifier in your OpenAPI query