A device type represents a particular make and model of hardware that exists in the real world. Device types define the physical attributes of a device (rack height and depth) and its individual components (console, power, network interfaces, and so on).
Device types are instantiated as devices installed within sites and/or equipment racks. For example, you might define a device type to represent a Juniper EX4300-48T network switch with 48 Ethernet interfaces. You can then create multiple instances of this type named "switch1," "switch2," and so on. Each device will automatically inherit the components (such as interfaces) of its device type at the time of creation. However, changes made to a device type will not apply to instances of that device type retroactively.
Some devices house child devices which share physical resources, like space and power, but which function independently. A common example of this is blade server chassis. Each device type is designated as one of the following:
A parent device (which has device bays)
A child device (which must be installed within a device bay)
This parent/child relationship is not suitable for modeling chassis-based devices, wherein child members share a common control plane. Instead, line cards and similarly non-autonomous hardware should be modeled as modules or inventory items within a device.
A device type may optionally specify an airflow direction, such as front-to-rear, rear-to-front, or passive. Airflow direction may also be set separately per device. If it is not defined for a device at the time of its creation, it will inherit the airflow setting of its device type.
A manufacturer represents the "make" of a device; e.g. Cisco or Dell. Each device type must be assigned to a manufacturer. (Inventory items and platforms may also be associated with manufacturers.) Each manufacturer must have a unique name and may have a description assigned to it.
Device Component Templates
Each device type is assigned a number of component templates which define the physical components within a device. These are:
- Console ports
- Console server ports
- Power ports
- Power outlets
- Network interfaces
- Front ports
- Rear ports
- Device bays (which house child devices)
Whenever a new device is created, its components are automatically created per the templates assigned to its device type. For example, a Juniper EX4300-48T device type might have the following component templates defined:
- One template for a console port ("Console")
- Two templates for power ports ("PSU0" and "PSU1")
- 48 templates for 1GE interfaces ("ge-0/0/0" through "ge-0/0/47")
- Four templates for 10GE interfaces ("xe-0/2/0" through "xe-0/2/3")
Once component templates have been created, every new device that you create as an instance of this type will automatically be assigned each of the components listed above.
Assignment of components from templates occurs only at the time of device creation. If you modify the templates of a device type, it will not affect devices which have already been created. However, you always have the option of adding, modifying, or deleting components on existing devices.
Console Port Templates
A template for a console port that will be created on all instantiations of the parent device type. Each console port can be assigned a physical type.
Console Server Port Templates
A template for a console server port that will be created on all instantiations of the parent device type. Each console server port can be assigned a physical type.
Power Port Templates
A template for a power port that will be created on all instantiations of the parent device type. Each power port can be assigned a physical type, as well as a maximum and allocated draw in watts.
Power Outlet Templates
A template for a power outlet that will be created on all instantiations of the parent device type. Each power outlet can be assigned a physical type, and its power source may be mapped to a specific feed leg and power port template. This association will be automatically replicated when the device type is instantiated.
A template for a network interface that will be created on all instantiations of the parent device type. Each interface may be assigned a physical or virtual type, and may be designated as "management-only." Power over Ethernet (PoE) mode and type may also be assigned to interface templates.
Front Port Templates
A template for a front-facing pass-through port that will be created on all instantiations of the parent device type. Front ports may have a physical type assigned, and must be associated with a corresponding rear port and position. This association will be automatically replicated when the device type is instantiated.
Rear Port Templates
A template for a rear-facing pass-through port that will be created on all instantiations of the parent device type. Each rear port may have a physical type and one or more front port templates assigned to it. The number of positions associated with a rear port determines how many front ports can be assigned to it (the maximum is 1024).
Module Bay Templates
A template for a module bay that will be created on all instantiations of the parent device type. Module bays hold installed modules that do not have an independent management plane, such as line cards.
Device Bay Templates
A template for a device bay that will be created on all instantiations of the parent device type. Device bays hold child devices, such as blade servers.