Configure a Loopback Interface
Table of Contents
Configure a Loopback Interface
Let us learn to configure a loopback interface.
| Where Can I Use This? | What Do I Need? |
|---|---|
|
|
Loopback is a logical, virtual interface used
to emulate a WAN port to provide LAN functionality. You can free up
a physical port previously used for LAN/WAN configuration by designating
a loopback interface. You can configure a maximum of four loopback
interfaces per device.
ION devices on versions 4.5.3 or
later at a site, support loopback interface. A loopback interface
can only be used as a WAN port on interfaces with no hardware bypass
circuitry. Interfaces with no hardware bypass circuitry per device
are as follows:
- ION 1000—All ports.
- ION 1200—All ports.
- ION 2000—Ports 1–3.
- ION 7000—Ports 1–4, 9–14.
- Virtual IONs—All non-controller ports.
A loopback
interface may be brought up or down administratively and may not
contain any sub-interfaces or IP configurations.
- You can update or delete a loopback interface. However, you cannot delete if it is part of a bypass pair.
- Decouple a port coupled with another port before a loopback interface can be coupled to create a bypass pair.
- The only valid option in the Use These Ports For drop-down is Private Layer 2 for a bypass pair that is made up of a physical LAN port and a loopback interface as the WAN port.
- The network policy rules assigned to such a site must not have any rules using the Direct on private WAN path. Valid paths are Direct on public or VPN on public. Traffic is dropped if a direct on private path is used.
- Select , select the device you want to configure.Select the Interfaces tab.On the interface configuration page for a device, click the + add icon to add a loopback interface and select Add.
![]()
For Admin Up, select No or Yes to administratively bring the interface up or down.Enter a Description and select Create Loopback.The system assigns a default loopback ID to the interface. A confirmation message displays that the loopback interface is successfully created.Next, select a port to be configured with a loopback interface.For Admin Up, select No or Yes to administratively bring the interface up or down. The default is Yes.(Optional) Enter a Description.From the Interface Type drop-down, select Bypass Pair.From the Pair With drop-down, select the Loopback Interface.A confirmation message displays.Select Done to create a bypass pair with the loopback interface successfully.A confirmation message displays the port's successful creation and the loopback interface.For Use These Ports For, select Private L2 from the drop-down.This is the only valid option for a bypass pair that is made of a physical LAN port and a loopback interface for the WAN port.Select the Circuit Label from the drop-down.(Optional) If you choose Copy Settings from Another Port, select the bypass pair to copy the settings. If not, you may leave it blank.Similar to configuring bypass pairs, for Attached Networks, enter a VLAN ID, IP Address at Router, optional Network Context, and toggle the scope tp Local or Global scope.Save Bypass Pair.The port and the loopback interface are displayed under Interfaces.![]()
