Properties of loopback interfaces

You create and configure a loopback interface at the network interface loopback level.

To create an interface, use the following command:

Admin@nodename# create network interface loopback

Parameters:

Parameter

Description

enabled

Enable/disable the interface:

  • on

  • off

interface-name

The interface name.

description

Network interface description.

alias

The interface's alias.

ip-addresses

Assign an IP address to the interface.

The IP addresses are specified as [ <ip_address/mask> ], the subnet mask is entered in the decimal format.

Important! Make sure to separate the square brackets with spaces on both sides.

iface-mode

IP address assignment mode:

  • dhcp: obtain a dynamic IP address via DHCP.

  • manual: no address.

Static mode is set automatically when an IP address is assigned to the interface.

lldp-profile

Profile to send data using Link Layer Discovery Protocol (LLDP). For more details on configuring profiles, see Configuring LLDP Profiles.

zone

Zone to which the interface belongs.

link-info

Settings for interface parameters:

  • bc_forwarding: control forwarding the directed broadcast packets arriving at the specified interface.

  • proxy_arp, proxy_arp_vlan: Proxy ARP mechanism. With proxy_arp, UserGate will respond to ARP requests for addresses outside the interface's network; with proxy_arp_vlan, UserGate will respond to ARP requests for addresses that belong to the interface's network.

To specify them, use the following format:

Admin@nodename# create network interface <iface-type> ... link-info [ key/value ]

where key is the parameter name. which can include lowercase Latin letters (a-z) and underscore (_), and

value is the parameter value. Parameter values can only be integers.

For example, use proxy_arp/1 to enable the Proxy ARP mechanism and proxy_arp/0 to disable it.

The link-info field is displayed only when adding parameters.

Important! You cannot delete the specified parameters.

netflow-profile

The Netflow profile to send statistical data to the Netflow collector. For more details on Netflow profile settings, see Configuring Netflow Profiles.

node-name

Cluster node where the interface is created.

mac

Interface MAC address.

mtu

Specify the MTU size.

dhcp-relay

Settings for the DHCP relay on the interface. You need to specify the following:

  • enabled: enable/disable the relay:

    • on

    • off

  • utm-address: IP address of the UserGate interface on which the relay function is added (possible values: <ip | none>).

  • server-address: addresses of DHCP servers where DHCP requests from clients should be redirected.

To edit an existing interface, use the following command:

Admin@nodename# set network interface loopback <interface-name>

The parameters available for setting are the same as those for creating a loopback interface, except for node-name and interface (you cannot change these parameter values).

To delete a loopback interface or its parameters, use the following command:

Admin@nodename# delete network interface loopback <interface-name>

You can delete the following parameters:

Parameter

Description

ip-addresses

Specified IP address.

dhcp-relay

DHCP server IP address.

To display information about all loopback interfaces, use the following command:

Admin@nodename# show network interface loopback

To display information about a single interface, use the following command:

Admin@nodename# show network interface loopback <interface-name>