Configuring And Displaying Layer 3 Interfaces - Foundry Networks NetIron M2404C User Manual

Foundry NetIron M2404C and M2404F Metro Access Switches

Configuring and Displaying Layer 3 Interfaces

When a host in one VLAN wants to communicate with a host in another VLAN, the traffic is
routed between them by creating Layer 3 Interfaces. A permanent Layer 3 interface (sw0) is
attached to VLAN 1 referred to as "default VLAN". All available ports in the system are attached
to this VLAN as untagged. For the device to be able to route between the VLANs, the Layer 3
interfaces must be configured with an IP address.
The lo1-lo9 Layer 3 interfaces are not directly related to a VLAN. These interfaces can never be in
a down state. The packets sent through them are looped back to the IP stack and are then routed on
a destination-IP-address basis.
The OutBand Layer 3 IP interface belongs to the Out-of-Band port. This port is destined for
debugging and management and cannot be used to pass data.
NOTE It is strongly recommended to use regular IP interfaces instead of OutBand
interfaces when debugging and management traffic is expected.
For more information on Configuring IP Unicast Routing, please see "Configuring Routing
Information".
Creating an IP Interface
The interface command, in Global Configuration mode, accesses the configuration mode of a
specific IP interface and creates the IP interface. The no form of this command removes the IP
interface.
The device changes to IP Interface Configuration mode, indicated by the change in the prompt-line
to (config-if IFNAME)#.
The interface command can also be entered in IP Interface Configuration mode, for selecting
another IP interface to configure.
Command Syntax
device-name(config)#interface {swN | outBand0 | loN}
device-name(config-if IFNAME)#interface {swN | outBand0 | loN}
device-name(config)#no interface {swN | loN}
Argument Description
swN
outBand0
loN
Example
device-name
device-name
Configuring and Displaying Layer 3 Interfaces
Number of the IP interface. The range is <0-255>.
Enters into the OutBand IP Interface Configuration mode.
Number of the loopback interface. The range is <1-9>.
(config)#interface sw3
(config-if sw3)#
© 2008 Foundry Networks, Inc.
Configuring Interfaces (Rev. 03)
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