By default the device discovery doesn't discover all elements and data from
this device, this is the case when a user want to monitor trunk group which
are configured locally on the device.
Enable those variables in the policy used to discover the device
Cisco - Discover Cisco Trunk Port InterfacesNH_DISCOVER_TRUNK_PORT
Cisco - Group VLANsNH_DISCOVER_CISCO_VLAN_GROUPS