HP StorageWorks 8000 - NAS User Manual page 201

Trap
hpHttpDeviceAddedTrap
hpHttpDeviceRemovedTrap
Sent whenever a device is added to the MIB. The key element in
this trap is the hpHttpMgDeviceIndex that allow the
management software to find the device easily and add it to the
managed environment. If there is no device management
software supported via a URL, both
hpHttpMgDeviceManagementURL and
hpHttpMgDeviceManagementURLLabel should be null.
Sent whenever a device is removed from the MIB. Key elements
in this trap are hpHttpMgDeviceIndex and
hpHttpMgDeviceSysObjID that allow the management software
to find the device easily and remove it from the managed
environment.
Definition
SNMP Trap Definitions 199