Users Guide

For information about how to install a PE and set up a PE stack, see the C1048P Getting Started Guide
and C1048P Installation Guide.
VLAN Interfaces
VLANs are logical interfaces and are, by default, in Layer 2 mode. Physical interfaces and port channels
can be members of VLANs. The supported VLAN range is 1 – 4094.
For more information about VLANs and Layer 2, refer to Layer 2 and Virtual LANs (VLANs).
NOTE: To monitor VLAN interfaces, use Management Information Base for Network Management of
TCP/IP-based internets: MIB-II (RFC 1213).
NOTE: You cannot simultaneously use egress rate shaping and ingress rate policing on the same
VLAN.
The system supports Inter-VLAN routing (Layer 3 routing in VLANs). You can add IP addresses to VLANs
and use them in routing protocols in the same manner that physical interfaces are used. For more
information about configuring different routing protocols, refer to the chapters on the specific protocol.
A consideration for including VLANs in routing protocols is that you must configure the no shutdown
command. (For routing traffic to flow, you must enable the VLAN.)
NOTE: You cannot assign an IP address to the default VLAN, which is VLAN 1 (by default). To assign
another VLAN ID to the default VLAN, use the default vlan-id vlan-id command.
To assign an IP address to an interface, use the following command.
• Configure an IP address and mask on the interface.
INTERFACE mode
ip address ip-address mask [secondary]
– ip-address mask: enter an address in dotted-decimal format (A.B.C.D). The mask must be in
slash format (/24).
– secondary: the IP address is the interface’s backup IP address. You can configure up to eight
secondary IP addresses.
Example of a Configuration for a VLAN Participating in an OSPF Process
interface Vlan 10
ip address 1.1.1.2/24
tagged TenGigabitEthernet 2/2-13
tagged TenGigabitEthernet 5/0
ip ospf authentication-key force10
ip ospf cost 1
ip ospf dead-interval 60
ip ospf hello-interval 15
no shutdown
!
Loopback Interfaces
A Loopback interface is a virtual interface in which the software emulates an interface. Packets routed to
it are processed locally.
Because this interface is not a physical interface, you can configure routing protocols on this interface to
provide protocol stability. You can place Loopback interfaces in default Layer 3 mode.
To configure, view, or delete a Loopback interface, use the following commands.
Interfaces
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