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Administration Guide

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Loopback

A loopback interface is a special virtual interface created in software that is not associated with any hardware interface.

Dynamic routing protocols typically use a loopback interface as a reliable IP interface for routing updates. You can assign the loopback IP address to the router rather than the IP address of a specific hardware interface. Services (such as Telnet) can access the router using the loopback IP address, which remains available independent of hardware interfaces status.

No limit exists on the number of loopback interfaces you can create.

A loopback interface does not have an internal VLAN ID or a MAC addresses and usually has a /32 network mask.

Using the GUI:
  1. Go to System > Network > Interface > Loopback.
  2. Select Add Interface.
  3. Enter a name for the loopback interface.
  4. Select Static for the mode and then enter the IP address and netmask in the IP/Netmask field.
  5. Select the protocols allowed to access the loopback interface.
  6. Select the administration status.
  7. Select Add.
Using the CLI:

config system interface

edit "loopback"

set ip 172.168.20.1 255.255.255.255

set allowaccess ping https http ssh telnet

set type loopback

set snmp-index 28

next

end

Loopback

A loopback interface is a special virtual interface created in software that is not associated with any hardware interface.

Dynamic routing protocols typically use a loopback interface as a reliable IP interface for routing updates. You can assign the loopback IP address to the router rather than the IP address of a specific hardware interface. Services (such as Telnet) can access the router using the loopback IP address, which remains available independent of hardware interfaces status.

No limit exists on the number of loopback interfaces you can create.

A loopback interface does not have an internal VLAN ID or a MAC addresses and usually has a /32 network mask.

Using the GUI:
  1. Go to System > Network > Interface > Loopback.
  2. Select Add Interface.
  3. Enter a name for the loopback interface.
  4. Select Static for the mode and then enter the IP address and netmask in the IP/Netmask field.
  5. Select the protocols allowed to access the loopback interface.
  6. Select the administration status.
  7. Select Add.
Using the CLI:

config system interface

edit "loopback"

set ip 172.168.20.1 255.255.255.255

set allowaccess ping https http ssh telnet

set type loopback

set snmp-index 28

next

end