Interfaces
Interfaces in NetBox represent network interfaces used to exchange data with connected devices. On modern networks, these are most commonly Ethernet, but other types are supported as well. IP addresses and VLANs can be assigned to interfaces.
Tip
Like most device components, interfaces are instantiated automatically from interface templates assigned to the selected device type when a device is created.
Note
Although both devices and virtual machines both can have interfaces assigned, a separate model is used for each. Thus, device interfaces have some properties that are not present on virtual machine interfaces and vice versa.
Fields
Device
The device to which this interface belongs.
Module
The installed module within the assigned device to which this interface belongs (optional).
Name
The name of the interface, as reported by the device's operating system. Must be unique to the parent device.
Label
An alternative physical label identifying the interface.
Type
The type of interface. Interfaces may be physical or virtual in nature, but only physical interfaces may be connected via cables. The generic channel type identifies a channelized subinterface bound to a parent interface when its specific transceiver type is not relevant; a channel subinterface may instead keep its own specific physical type (e.g. directly declaring a channel as 10GBASE-SR) to record the actual transceiver in use.
Note
The interface type refers to the physical termination or port on the device. Interfaces which employ a removable optic or similar transceiver should be defined to represent the type of transceiver in use, irrespective of the physical termination to that transceiver.
Channels
This field was added in NetBox v4.7.
For a channelized (breakout) interface, the number of physical channels into which the interface is divided. For example, a 40GE interface broken out into four 10GE channels would have channels set to four. Each channel is modeled as a channel subinterface bound to this interface via its channel ID.
A single physical cable terminates to the channelized (parent) interface, occupying one connector shared by all of its channels; NetBox traces a distinct cable path for each channel subinterface. Only one layer of channelization is supported: an interface cannot be both channelized and itself bound to a channel.
Speed
The operating speed, in kilobits per second (kbps).
Duplex
The operation duplex (full, half, or auto).
VRF
The virtual routing and forwarding instance to which this interface is assigned.
Primary MAC Address
The MAC address assigned to this interface which is designated as its primary.
MAC address is a property
The MAC address of an interface (formerly a concrete database field) is available as a property, mac_address, which reflects the value of the primary linked MAC address object.
WWN
The 64-bit world-wide name (for Fibre Channel interfaces).
MTU
The interface's configured maximum transmissible unit (MTU).
Transmit Power
The interface's configured output power, in dBm (for optical interfaces).
Enabled
If not selected, this interface will be treated as disabled/inoperative.
Management Only
Designates the interface as handling management traffic only (e.g. for out-of-band management connections).
Mark Connected
If selected, this component will be treated as if a cable has been connected.
Parent Interface
Virtual interfaces can be bound to a physical parent interface. This is helpful for modeling virtual interfaces which employ encapsulation on a physical interface, such as an 802.1Q VLAN-tagged subinterface. A channel subinterface is likewise bound to its channelized parent interface, whether it uses the generic channel type or its own specific physical type.
Note
An interface with one or more child interfaces assigned cannot be deleted until all its child interfaces have been deleted or reassigned. Renaming a channelized interface updates the names of any channel subinterfaces which follow the <name>:<channel ID> convention, to keep their names consistent with their new parent, unless the resulting name is already in use by another interface on the device or would exceed the maximum length of the name field (in either case, that subinterface's name is left unchanged).
Channel ID
The numeric channel on a channelized parent interface to which this subinterface is bound, identifying it as a channel subinterface. This may be set on the generic channel type, or on any other physical interface type (e.g. to record the specific transceiver used on that channel) — but not on a virtual or wireless interface. The channel ID must fall within the range of channels provided by the parent (e.g. one through four for a parent with four channels). A channel subinterface derives its cable connection from the parent's; it cannot be cabled directly.
Channel IDs are one-indexed
Channel IDs increment starting at one, even for interfaces with a zero-based identifier. This ensures that each subinterface maps cleanly to the profile of an attached cable.
Bridged Interface
Interfaces can be bridged to other interfaces on a device in two manners: symmetric or grouped.
- Symmetric: For example, eth0 is bridged to eth1, and eth1 is bridged to eth0. This effects a point-to-point bridge between the two interfaces, which NetBox will follow when tracing cable paths.
- Grouped: Multiple interfaces are each bridged to a common virtual bridge interface, effecting a multiaccess bridged segment. NetBox cannot follow these relationships when tracing cable paths, because no forwarding information is available.
LAG Interface
Physical interfaces may be arranged into link aggregation groups (LAGs, also known as "trunks") and associated with a parent LAG (virtual) interface. LAG interfaces can be recursively nested to model bonding of trunk groups. Like all virtual interfaces, LAG interfaces cannot be connected physically.
PoE Mode
The power over Ethernet (PoE) mode for this interface. (This field must be left empty for interfaces which do not support PoE.) Choices include:
- Powered device (PD)
- Power-supplying equipment (PSE)
PoE Type
The classification of PoE transmission supported, for PoE-enabled interfaces. This can be one of the listed IEEE 802.3 standards, or a passive setting (24 or 48 volts across two or four pairs).
802.1Q Mode
For switched Ethernet interfaces, this identifies the 802.1Q encapsulation strategy in effect. Options include:
- Access: All traffic is assigned to a single VLAN, with no tagging.
- Tagged: One untagged "native" VLAN is allowed, as well as any number of tagged VLANs.
- Tagged (all): Implies that all VLANs are carried by the interface. One untagged VLAN may be designated.
- Q-in-Q: Q-in-Q (IEEE 802.1ad) encapsulation is performed using the assigned SVLAN.
This field must be left blank for routed interfaces which do employ 802.1Q encapsulation.
Untagged VLAN
The "native" (untagged) VLAN for the interface. Valid only when one of the above 802.1Q mode is selected.
Tagged VLANs
The tagged VLANs which are configured to be carried by this interface. Valid only for the "tagged" 802.1Q mode above.
Q-in-Q SVLAN
The assigned service VLAN (for Q-in-Q/802.1ad interfaces).
Wireless Role
Indicates the configured role for wireless interfaces (access point or station).
Wireless Channel
The configured channel for wireless interfaces.
Tip
Selecting one of the pre-defined wireless channels will automatically populate the channel frequency and width upon saving the interface.
Channel Frequency
The configured operation frequency of a wireless interface, in MHz. This is typically inferred by the configured channel above, but may be set manually e.g. to identify a licensed channel not available for general use.
Channel Width
The configured channel width of a wireless interface, in MHz. This is typically inferred by the configured channel above, but may be set manually e.g. to identify a licensed channel not available for general use.
Wireless LANs
The wireless LANs for which this interface carries traffic. (Valid for wireless interfaces only.)
VLAN Translation Policy
The VLAN translation policy that applies to this interface (optional).