You can create sub-interfaces on physical
or virtual interfaces and use bypass pairs for Local Area Networks (LANs)
and private and public Wide Area Networks (WANs). A sub-interface
is created by dividing one physical interface into multiple virtual
The parent interface can be an Ethernet port,
a virtual port, or a bypass pair that does not contain any configuration.
You cannot configure a sub-interface on the controller port or any
interfaces or bypass pairs already configured with loopback as a
member with PPPoE or standard VPNs.
If the sub-interface
is on a bypass pair and the sub-interface is used for internet or
private WAN, then the sub-interface is created on the bypass pair's
If the sub-interface is on a bypass pair and the sub-interface
is used for LAN, then the sub-interface is created on the LAN port of
the bypass pair.
Multiple sub-interfaces may be configured
on a physical or virtual interface or bypass pairs. If multiple
interfaces are configured, a VLAN ID is required to create and uniquely
identify each sub-interface.
LAN sub-interfaces may only be used for the following branch services.
5.1.1 and later
device releases enable LAN sub-interfaces to
forward user and application traffic in addition to the following
DHCP Relay source interface
SNMP Trap source interface
Ping to and from the interface IP
Secure Socket Shell (SSH) access to the ION device CLI commands
cannot configure a Virtual Interface (VI) on a sub-interface. DHCP
Relay and DHCP server cannot be configured on the same sub-interface.
DHCP Relay when configured on a sub-interface:
to broadcast and unicast DHCP requests.
Can use the sub-interface as the source interface to reach DHCP
When SNMP is configured on a sub-interface:
An SNMP Agent can listen to unicast requests.
An SNMP Trap can use the sub-interface as the source interface
to reach SNMP servers.
, select a device
Configure the device
Select a port.
Use This Port To
+ Add Sub-Interface
create a new sub-interface.
Use This Sub-Interface To
select the option applicable to the interface you are configuring;
Peer with a Network
, select circuits
The VLAN ID can be updated or changed.
Mark the Native VLAN box if the identified sub-interface
is used for native VLAN.
Only one sub-interface of a parent interface can be configured
for native VLAN. By default, the native VLAN box is unchecked.
DNS Servers need to be entered for Internet and Private
WAN but not for LAN.