Interfaces Configuration Guide, Cisco DCNM for LAN, Release 5.x
Configuring Layer 3 Interfaces
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Configuring Layer 3 Interfaces

Table Of Contents

Configuring Layer 3 Interfaces

Information About Layer 3 Interfaces

Routed Interfaces

Subinterfaces

VLAN Interfaces

Loopback Interfaces

Tunnel Interfaces

High Availability

Virtualization Support

Licensing Requirements for Layer 3 Interfaces

Prerequisites for Layer 3 Interfaces

Platform Support

Configuring Layer 3 Interfaces

Configuring a Routed Interface

Configuring an IPv4 Secondary Address or Helper Address

Configuring an IPv6 Secondary Address

Configuring a Subinterface

Deleting a Subinterface

Creating a Port-Channel Subinterface

Deleting a Port-Channel Subinterface

Configuring the Bandwidth on an Interface

Configuring a VLAN Network Interface

Deleting a VLAN Network Interface

Configuring a Loopback Interface

Deleting a Loopback Interface

Monitoring Layer 3 Interfaces

Related Topics

Field Descriptions for Layer 3 Interfaces

Routed Interfaces

Loopback

Loopback: Details Tab: Basic Settings Section

Loopback: Details Tab: IP Address Settings Section

Loopback: Statistics Tab

VLAN Network Interface

VLAN Network Interface: Details Tab: Basic Settings Section

VLAN Network Interface: Details Tab: IP Address Settings Section

VLAN Network Interface: Statistics Tab

Additional References

Related Documents

MIBs

Standards

Feature History for Configuring Layer 3 Interfaces


Configuring Layer 3 Interfaces


This chapter describes how to configure Layer 3 interfaces using Cisco Data Center Network Manager (DCNM).

This chapter includes the following sections:

Information About Layer 3 Interfaces

Licensing Requirements for Layer 3 Interfaces

Prerequisites for Layer 3 Interfaces

Configuring Layer 3 Interfaces

Monitoring Layer 3 Interfaces

Related Topics

Field Descriptions for Layer 3 Interfaces

Additional References

Feature History for Configuring Layer 3 Interfaces

Information About Layer 3 Interfaces


Note The Cisco NX-OS release that is running on a managed device may not support all the features or settings described in this chapter. For the latest feature information and caveats, see the documentation and release notes for your platform and software release.

Layer 3 interfaces forward IPv4 and IPv6 packets to another device using static or dynamic routing protocols. You can use Layer 3 interfaces for IP routing and inter-VLAN routing of Layer 2 traffic.

You cannot configure a shared interface as a Layer 3 interface. See the Cisco NX-OS FCoE Configuration Guide for Cisco Nexus 7000 and Cisco MDS 9500 for information on shared interfaces.

This section includes the following topics:

Routed Interfaces

Subinterfaces

VLAN Interfaces

Loopback Interfaces

Tunnel Interfaces

High Availability

Virtualization Support

Routed Interfaces

You can configure a port as a Layer 2 interface or a Layer 3 interface. A routed interface is a physical port that can route IP traffic to another device. A routed interface is a Layer 3 interface only and does not support Layer 2 protocols, such as the Spanning Tree Protocol (STP).

All Ethernet ports are routed interfaces by default. You can change this default behavior with the CLI setup script.

You can assign an IP address to the port, enable routing, and assign routing protocol characteristics to this routed interface.

You can also create a Layer 3 port channel from routed interfaces. For more information on port channels, see Chapter 5 "Configuring Port Channels."

Routed interfaces and subinterfaces support exponentially decayed rate counters. Cisco NX-OS tracks the following statistics with these averaging counters:

Input packets/sec

Output packets/sec

Input bytes/sec

Output bytes/sec

Subinterfaces

You can create virtual subinterfaces on a parent interface configured as a Layer 3 interface. A parent interface can be a physical port or a port channel.

Subinterfaces divide the parent interface into two or more virtual interfaces on which you can assign unique Layer 3 parameters such as IP addresses and dynamic routing protocols. The IP address for each subinterface should be in a different subnet from any other subinterface on the parent interface.

You create a subinterface with a name that consists of the parent interface name (for example, Ethernet 2/1) followed by a period and then by a number that is unique for that subinterface. For example, you could create a subinterface for Ethernet interface 2/1 named Ethernet 2/1.1 where .1 indicates the subinterface.

Cisco NX-OS enables subinterfaces when the parent interface is enabled. You can shut down a subinterface independent of shutting down the parent interface. If you shut down the parent interface, Cisco NX-OS shuts down all associated subinterfaces as well.

One use of subinterfaces is to provide unique Layer 3 interfaces to each virtual local area network (VLAN) supported by the parent interface. In this scenario, the parent interface connects to a Layer 2 trunking port on another device. You configure a subinterface and associate the subinterface to a VLAN ID using 802.1Q trunking.

Figure 4-1 shows a trunking port from a switch that connects to router B on interface E 2/1. This interface contains three subinterfaces that are associated with each of the three VLANs carried by the trunking port.

Figure 4-1 Subinterfaces for VLANs

For more information on VLANs, see the Layer 2 Switching Configuration Guide, Cisco DCNM for LAN, Release 5.x.

VLAN Interfaces

A VLAN network interface is a virtual routed interface that connects a VLAN on the device to the Layer 3 router engine on the same device. Only one VLAN network interface can be associated with a VLAN, but you need to configure a VLAN network interface for a VLAN only when you wish to route between VLANs or to provide IP host connectivity to the device through a virtual routing and forwarding (VRF) instance that is not the management VRF. When you enable VLAN network interface creation, NX-OS creates a VLAN network interface for the default VLAN (VLAN 1) to permit remote switch administration.

You must enable the VLAN network interface feature before you can see configure it. Beginning in Release 4.2, the system automatically takes a checkpoint prior to disabling the feature, and you can rollback to this checkpoint. See Cisco Nexus 7000 Series NX-OS System Management Configuration Guide, Release 5.x, for information on rollbacks and checkpoints.


Note You cannot delete the VLAN interface for VLAN 1.

You can route across VLAN interfaces to provide Layer 3 inter-VLAN routing by configuring a VLAN interface for each VLAN that you want to route traffic to and assigning an IP address on the VLAN interface. For more information on IP addresses and IP routing, see the Unicast Configuration Guide, Cisco DCNM for LAN, Release 5.x.

Figure 4-2 shows two hosts connected to two VLANs on a device. You can configure VLAN interfaces for each VLAN that allows Host 1 to communicate with Host 2 using IP routing between the VLANs. VLAN 1 communicates at Layer 3 over VLAN interface 1and VLAN 10 communicates at Layer 3 over VLAN interface 10.

Figure 4-2 Connecting Two VLANs with VLAN interfaces


Note You can configure VLAN interface for inband management in the Cisco Nexus 7000 Series switches with the F1 Series modules in the chassis.

Loopback Interfaces

A loopback interface is a virtual interface with a single endpoint that is always up. Any packet transmitted over a loopback interface is immediately received by this interface. Loopback interfaces emulate a physical interface. You can configure up to 1024 loopback interfaces per VDC, numbered 0 to 1023.

You can use loopback interfaces for performance analysis, testing, and local communications. Loopback interfaces can act as a termination address for routing protocol sessions. This loopback configuration allows routing protocol sessions to stay up even if some of the outbound interfaces are down.

Tunnel Interfaces

Cisco DCNM supports tunnel interfaces as IP tunnels. IP tunnels can encapsulate a same-layer or higher layer protocol and transport the result over IP through a tunnel created between two routers. See Chapter 7 "Configuring IP Tunnels," for more information on IP tunnels.

High Availability

Layer 3 interfaces support stateful and stateless restarts. After the switchover, Cisco NX-OS applies the runtime configuration after the switchover.

See the Cisco Nexus 7000 Series NX-OS High Availability and Redundancy Guide, Release 5.x, for complete information on high availability.

Virtualization Support

Layer 3 interfaces support Virtual Routing and Forwarding instances (VRFs). VRFs exist within virtual device contexts (VDCs). By default, Cisco NX-OS places you in the default VDC and default VRF unless you specifically configure another VDC and VRF. A Layer 3 logical interface (VLAN interface, loopback) configured in one VDC is isolated from a Layer 3 logical interface with the same number configured in another VDC. For example, loopback 0 in VDC 1 is independent of loopback 0 in VDC 2.

You can configure up to 1024 loopback interfaces per VDC.

You can associate the interface with a VRF. For VLAN interfaces, you must configure the VLAN interface in the same VDC as the VLAN.

See the Virtual Device Context Configuration Guide, Cisco DCNM for LAN, Release 5.x, for information about VDCs and see the Unicast Configuration Guide, Cisco DCNM for LAN, Release 5.x, for information about configuring an interface in a VRF.


Note You must assign an interface to a VRF before you configure the IP address for that interface.

Licensing Requirements for Layer 3 Interfaces

The following table shows the licensing requirements for this feature:

Product
License Requirement

Cisco DCNM

Layer 3 interfaces require no license.

Cisco NX-OS

Layer 3 interfaces require no license. Any feature not included in a license package is bundled with the Cisco NX-OS system images and is provided at no extra charge to you. For a complete explanation of the Cisco NX-OS licensing scheme, see the Cisco NX-OS Licensing Guide.


Prerequisites for Layer 3 Interfaces

Layer 3 interfaces have the following prerequisites:

You have installed the Advanced Services license and entered the desired VDC (see the Virtual Device Context Configuration Guide, Cisco DCNM for LAN, Release 5.x, if you are configuring VDCs.

You are familiar with IP addressing and basic configuration. See the Unicast Configuration Guide, Cisco DCNM for LAN, Release 5.x, for more information on IP addressing.

Platform Support

The following platform supports this feature. For platform-specific information, including guidelines and limitations, system defaults, and configuration limits, see the corresponding documentation.

Platform
Documentation

Cisco Nexus 3000 Series Switches

Cisco Nexus 3000 Series Switches Documentation

Cisco Nexus 7000 Series Switches

Cisco Nexus 7000 Series Switches Documentation

Cisco Catalyst 6500 Series Switches

Cisco Catalyst 6500 Series Switches Documentation


Configuring Layer 3 Interfaces

You can access Layer 3 interfaces from the Interfaces feature selection. Figure 4-3 shows the Layer 3 interfaces.

Figure 4-3 Configuring Layer 3 Interfaces

For more information about the Data Center Network Manager features, see the Fundamentals Configuration Guide, Cisco DCNM for LAN, Release 5.x

This section includes the following topics:

Configuring a Routed Interface

Configuring an IPv4 Secondary Address or Helper Address

Configuring an IPv6 Secondary Address

Configuring a Subinterface

Deleting a Subinterface

Creating a Port-Channel Subinterface

Deleting a Port-Channel Subinterface

Configuring the Bandwidth on an Interface

Configuring a VLAN Network Interface

Deleting a VLAN Network Interface

Configuring a Loopback Interface

Deleting a Loopback Interface

Configuring a Routed Interface

You can configure any Ethernet port as a routed interface.

DETAILED STEPS


Step 1 From the Feature Selector pane, choose Interfaces > Physical > Ethernet.

The available devices appear in the Summary pane (see Figure 4-3).

Step 2 From the Summary pane, double-click the device to display a list of slots.

Step 3 Double-click the slot to display a list of interfaces.

Step 4 Click the interface that you want to configure as a routed interface.

The system highlights the interface in the Summary pane, and tabs appear in the Details pane.

Step 5 From the Details pane, click the Port Details tab.

The Port Details tab appears.

Step 6 From the Port Details tab, expand the Port Mode Settings section.

The port mode appears.

Step 7 From the Mode drop-down list, choose Routed.

The IP address information appears in the Details pane and NX-OS removes any Layer 2 configuration.

Step 8 (Optional) From the IPv4 Address Settings, set the Primary field to the IPv4 address for this routed interface.

Step 9 (Optional) Set the Net mask field to the network mask for this IPv4 address in dotted decimal notation.

Step 10 (Optional) From the IPv6 Address Settings area, set the Primary/Prefix-length field to the IPv6 address and prefix length for this routed interface.

The length range is from 1 to 128.

Step 11 (Optional) To set EUI64, check EUI64.

Step 12 (Optional) From the Link Local field, enter the link local IPv6 address.

Step 13 (Optional) To set this routed interface for link-local routing only, check Use local only.

Step 14 From the menu bar, choose File > Deploy to apply your changes to the device.


Configuring an IPv4 Secondary Address or Helper Address

You can configure secondary addresses or helper addresses for an interface.

DETAILED STEPS


Step 1 From the Feature Selector pane, choose Interfaces > Physical > Ethernet.

The available devices appear in the Summary pane (see Figure 4-3).

Step 2 From the Summary pane, double-click the device to display a list of slots.

Step 3 Double-click the slot to display a list of interfaces.

Step 4 Click the interface that you want to configure as a routed interface.

The system highlights the interface in the Summary pane, and tabs appear in the Details pane.

Step 5 From the Details pane, click the Port Details tab.

The Port Details tab appears.

Step 6 From the Port Details tab, expand the Port Mode Settings section.

The port mode appears.

Step 7 (Optional) From the IPv4 Address settings section, in the Secondary area, right-click and choose Add Secondary IP to add a secondary IP address.

Step 8 From the secondary area, in the IP address field, enter an IPv4 address.

Step 9 From the net mask field, enter the network mask for this IPv4 address in dotted decimal notation.

Step 10 (Optional) From the IPv4 Address settings section, in the Helper area, right-click and choose Add Helper IP to add a DHCP helper IP address.

Step 11 From the Helper area, in the IP address field, enter an IPv4 address.

Step 12 From the menu bar, choose File > Deploy to apply your changes to the device.


Configuring an IPv6 Secondary Address

You can configure secondary addresses or helper addresses for an interface.

DETAILED STEPS


Step 1 From the Feature Selector pane, choose Interfaces > Physical > Ethernet.

The available devices appear in the Summary pane (see Figure 4-3).

Step 2 From the Summary pane, double-click the device to display a list of slots.

Step 3 Double-click the slot to display a list of interfaces.

Step 4 Click the interface that you want to configure as a routed interface.

The system highlights the interface in the Summary pane, and tabs appear in the Details pane.

Step 5 From the Details pane, click the Port Details tab.

The Port Details tab appears.

Step 6 From the Port Details tab, expand the Port Mode Settings section.

The port mode appears.

Step 7 From the IPv6 Address settings section, in the Secondary area, right-click and choose Add IPv6 Address to add a secondary IPv6 address.

Step 8 From the IP Address/Prefix-length field, enter the IPv6 address and prefix length for this secondary IPv6 address.

Step 9 (Optional) To set EUI64, check EUI64.

Step 10 From the menu bar, choose File > Deploy to apply your changes to the device.


Configuring a Subinterface

You can configure one or more subinterfaces on a routed interface or on a port channel made from routed interfaces.

BEFORE YOU BEGIN

Configure the parent interface as a routed interface.

See the "Configuring a Routed Interface" section.

Create the port-channel interface if you want to create a subinterface on that port channel (see the "Configuring Port Channels" section).

DETAILED STEPS


Step 1 From the Feature Selector pane, choose Interfaces > Physical > Ethernet.

The available devices appear in the Summary pane.

Step 2 From the Summary pane, double-click the device to display a list of slots.

Step 3 Double-click the slot to display a list of interfaces.

Step 4 Click the interface that you want to configure a subinterface on.

The system highlights the interface in the Summary pane, and tabs appear in the Details pane.

Step 5 From the menu bar, choose Actions > Add Subinterface to create a subinterface.

The system highlights the subinterface in the Summary pane, and tabs update in the Details pane.

Step 6 From the highlighted subinterface field, enter the subinterface number.

The range is from 1 to 4093.

Step 7 From the Details pane, click the Port Details tab.

The Port Details tab appears.

Step 8 From the Port Details tab, expand the Basic Settings section.

The basic interface information appears in the Details pane.

Step 9 From the encapsulation area, in the Vlan Id drop-down list, choose the VLAN ID that you want to associate this subinterface with.

Step 10 From the Port Details tab, expand the IP Address Settings section.

The IP address information appears in the Details pane.

Step 11 (Optional) From the IPv4 Address Settings, set the Primary field to the IPv4 address for this subinterface.

Step 12 (Optional) From the Net mask field, set the network mask for this IPv4 address in dotted decimal notation.

Step 13 (Optional) From the IPv6 Address Settings area, set the Primary/Prefix-length field to the IPv6 address and prefix length for this subinterface.

The length range is from 1 to 128.

Step 14 (Optional) To set EUI64, check EUI64.

Step 15 (Optional) From the Link Local field, enter the link local IPv6 address.

Step 16 (Optional) To set this subinterface for link-local routing only, check Use local only.

Step 17 From the menu bar, choose File > Deploy to apply your changes to the device.


Deleting a Subinterface

You can delete a subinterface.

DETAILED STEPS


Step 1 From the Feature Selector pane, choose Interfaces > Physical > Ethernet.

The available devices appear in the Summary pane.

Step 2 From the Summary pane, double-click the device to display a list of slots.

Step 3 Double-click the slot to display a list of interfaces.

Step 4 Click the interface that you want to delete a subinterface on.

The system highlights the interface in the Summary pane, and tabs appear in the Details pane.

Step 5 Click the subinterface that you want to delete.

The system highlights the subinterface in the Summary pane.

Step 6 From the menu bar, choose Actions > Delete Subinterface to delete this subinterface.

Step 7 From the menu bar, choose File > Deploy to apply your changes to the device.


Creating a Port-Channel Subinterface

You can create a port-channel subinterface.

DETAILED STEPS


Step 1 From the Feature Selector pane, choose Interfaces > Logical > Port Channel.

The available devices appear in the Summary pane.

Step 2 From the Summary pane, double-click the device to display a list of existing port channels.

Step 3 Right-click the port channel that you want to configure a subinterface on and choose New > Subinterface.

The system highlights the port channel subinterface in the Summary pane, and tabs appear in the Details pane.

Step 4 From the highlighted Channel Id field, enter the subinterface number.

The range is from 1 to 4093.

Step 5 From the Details pane, click the Port Channels Details tab.

The Details tab appears.

Step 6 From the Details tab, expand the Basic Settings section.

The basic interface information appears in the Details pane.

Step 7 (Optional) From the VLAN ID drop-down list, choose the VLAN ID that you want to associate this subinterface with.

Step 8 From the Details tab, expand the IP Address Settings section.

The IP address information appears in the Details pane.

Step 9 (Optional) From the IPv4 Address Settings, set the IP Address field to the IPv4 address for this subinterface.

Step 10 (Optional) From the Net Mask field, set the network mask for this IPv4 address in dotted decimal notation.

Step 11 (Optional) From the IPv6 Address Settings area, set the Primary/Prefix-length field to the IPv6 address and prefix length for this subinterface.

The length range is from 1 to 128.

Step 12 (Optional) To set EUI64, check EUI64.

Step 13 (Optional) From the Link Local field, enter the link local IPv6 address.

Step 14 (Optional) To set this subinterface for link-local routing only, check Use local only.

Step 15 From the menu bar, choose File > Deploy to apply your changes to the device.


Deleting a Port-Channel Subinterface

You can delete a port-channel subinterface.

DETAILED STEPS


Step 1 From the Feature Selector pane, choose Interfaces > Logical > Port Channel.

The available devices appear in the Summary pane.

Step 2 From the Summary pane, double-click the device to display a list of port channels.

Step 3 Click the port channel that you want to delete a subinterface on.

The system highlights the interface in the Summary pane, and tabs appear in the Details pane.

Step 4 Click the subinterface that you want to delete.

The system highlights the subinterface in the Summary pane.

Step 5 From the menu bar, choose Actions > Delete to delete this subinterface.

Step 6 From the menu bar, choose File > Deploy to apply your changes to the device.


Configuring the Bandwidth on an Interface

You can configure the bandwidth for a routed interface, port channel, or subinterface. Higher layer protocols use bandwidth parameter to calculate path costs. You can configure the bandwidth on a subinterface with one of the following methods:

Explicit—Set the bandwidth value for the subinterface directly.

Inherit—Set the bandwidth that all subinterfaces inherit from the parent interface as either a specific value or as the bandwidth of the parent interface.

If you do not set the subinterface bandwidth or configure it to inherit the bandwidth from the parent interface, Cisco NX-OS determines the subinterface bandwidth as follows:

If the parent interface is up, then the bandwidth of the subinterface is the same as the operational speed of the parent interface. For ports, the subinterface bandwidth is the configured or negotiated link speed. For port channels, the subinterface bandwidth is the aggregate of the link speeds of individual members of the port channel.

If the parent interface is down, then the bandwidth of the subinterface depends on the type of parent interface:

Port-channel subinterfaces have 100-Mb/s bandwidth for subinterfaces.

1-Gb/s Ethernet ports have 1-Gb/s bandwidth for subinterfaces.

10-Gb/s Ethernet ports have 10-Gb/s bandwidth for subinterfaces.

DETAILED STEPS


Step 1 From the Feature Selector pane, choose Interfaces > Physical > Ethernet.

The available devices appear in the Summary pane (see Figure 4-3).

Step 2 From the Summary pane, double-click the device to display a list of slots.

Step 3 Double-click the slot to display a list of interfaces.

Step 4 Click the interface that you want to configure the bandwidth on.

The system highlights the interface in the Summary pane, and tabs appear in the Details pane.

Step 5 From the Details pane, click the Port Details tab.

The Port Details tab appears.

Step 6 From the Port Details tab, expand the Basic Settings section.

The basic settings appears.

Step 7 In the Bandwidth (kb) field, enter the bandwidth value.

Step 8 From the menu bar, choose File > Deploy to apply your changes to the device.


Configuring a VLAN Network Interface

You can create VLAN interfaces to provide inter-VLAN routing.

DETAILED STEPS


Step 1 From the Feature Selector pane, choose Interfaces > Logical > VLAN Network Interface.

The available devices appear in the Summary pane.

Step 2 From the Summary pane, double-click the device to display a list of existing VLAN network interfaces.

Step 3 From the Details pane, click the Enable VLAN Network Interface Service link if present.

Step 4 From the menu bar, choose Actions > New > Add VLAN Network Interface.

The system highlights the new VLAN Network Interface in the Summary pane, and tabs appear in the Details pane.

Step 5 From the highlighted VLAN network interface field, enter the VLAN network interface number.

The number range is from 1 to 4094.

Step 6 From the Details pane, click the Details tab.

The Details tab appears.

Step 7 From the Details tab, expand the IP Address Settings section.

The IP address information appears in the Details pane.

Step 8 (Optional) From the IPv4 Address Settings, set the Primary field to the IPv4 address for this VLAN network interface.

Step 9 (Optional) From the Net Mask field, set the network mask for this IPv4 address in dotted decimal notation.

Step 10 (Optional) From the IPv6 Address Settings area, set the Primary/Prefix-length field to the IPv6 address and prefix length for this VLAN network interface.

The length range is from 1 to 128.

Step 11 (Optional) To set EUI64, check EUI64.

Step 12 (Optional) From the Link Local field, enter the link local IPv6 address.

Step 13 (Optional) To set this VLAN network interface for link-local routing only, check Use local only.

Step 14 From the menu bar, choose File > Deploy to apply your changes to the device.


Deleting a VLAN Network Interface

You can delete a VLAN network interface.

DETAILED STEPS


Step 1 From the Feature Selector pane, choose Interfaces > Logical > VLAN Network Interface.

The available devices appear in the Summary pane.

Step 2 From the Summary pane, double-click the device to display a list of existing VLAN network interfaces.

Step 3 Click the VLAN network interface that you want to delete.

The system highlights the VLAN network interface in the Summary pane, and tabs appear in the Details pane.

Step 4 From the menu bar, choose Actions > Delete VLAN Network Interface to delete this VLAN network interface.

Step 5 From the menu bar, choose File > Deploy to apply your changes to the device.


Configuring a Loopback Interface

You can configure a loopback interface to create a virtual interface that is always up.

BEFORE YOU BEGIN

Ensure that the IP address of the loopback interface is unique across all routers on the network.

DETAILED STEPS


Step 1 From the Feature Selector pane, choose Interfaces > Logical > Loopback.

The available devices appear in the Summary pane.

Step 2 From the Summary pane, double-click the device to display a list of existing loopback interfaces.

Step 3 From the menu bar, choose Actions > New > Add Loopback Interface.

The system highlights the new loopback interface in the Summary pane, and tabs appear in the Details pane.

Step 4 From the highlighted loopback field, enter the loopback number.

The number range is from 1 to 4094.

Step 5 From the Details pane, click the Details tab.

The Details tab appears.

Step 6 From the Details tab, expand the IP Address Settings section.

The IP address information appears in the Details pane.

Step 7 (Optional) From the IPv4 Address Settings, set the Primary field to the IPv4 address for this loopback interface.

Step 8 (Optional) From the Net Mask field, set the network mask for this IPv4 address in dotted decimal notation.

Step 9 (Optional) From the IPv6 Address Settings area, set the Primary/Prefix-length field to the IPv6 address and prefix length for this loopback interface.

The length range is from 1 to 128.

Step 10 (Optional) To set EUI64, check EUI64.

Step 11 (Optional) From the Link Local field, enter the link local IPv6 address.

Step 12 (Optional) To set this loopback interface for link-local routing only, check Use local only.

Step 13 From the menu bar, choose File > Deploy to apply your changes to the device.


Deleting a Loopback Interface

You can delete a loopback interface.

DETAILED STEPS


Step 1 From the Feature Selector pane, choose Interfaces > Logical > Loopback.

The available devices appear in the Summary pane.

Step 2 From the Summary pane, double-click the device to display a list of existing loopback interfaces.

Step 3 Click the loopback interface that you want to delete.

The system highlights the loopback interface in the Summary pane, and tabs appear in the Details pane.

Step 4 From the menu bar, choose Actions > Delete Loopback Interface to delete this loopback interface.

Step 5 From the menu bar, choose File > Deploy to apply your changes to the device.


Monitoring Layer 3 Interfaces

You can configure DCNM to collect layer 3 interface statistics. Choose Interfaces from the Feature Selector and navigate to the interface that you want to collect statistics on.

The following windows appear in the Statistics tab:

Port Traffic Statistics—Collects input and output (packet and byte) counters, broadcast, multicast, and unicast traffic.

Port Error Statistics—(physical ports only) Collects a variety of error statistics for the interface.

See the Fundamentals Configuration Guide, Cisco DCNM for LAN, Release 5.x , for more information on collecting statistics for Layer 3 interfaces.

Related Topics

The following topics can give more information on Layer 3 interfaces:

Chapter 5 "Configuring Port Channels"

Unicast Configuration Guide, Cisco DCNM for LAN, Release 5.x

Field Descriptions for Layer 3 Interfaces

This section includes the following field descriptions for layer 3 interfaces:

Routed Interfaces

Loopback

VLAN Network Interface

Routed Interfaces

Field descriptions for routed interfaces are covered in Chapter 2 "Configuring Basic Interface Parameters."

Loopback

This section includes the following field descriptions for loopback interfaces:

Loopback: Details Tab: Basic Settings Section

Loopback: Details Tab: IP Address Settings Section

Loopback: Statistics Tab

VLAN Network Interface

Loopback: Details Tab: Basic Settings Section

Table 4-1 Loopback: Details: Basic Settings 

Field
Description

Name

Display only. Name of the loopback interface.

Description

String that describes the loopback interface.

Admin Status

Administrative status of the loopback interface. The default is up.


Loopback: Details Tab: IP Address Settings Section

Table 4-2 Loopback: Details: IP Address Settings 

Field
Description
IPv4 Address Settings

Primary

IPv4 address in dotted decimal notation.

Net Mask

Network mask for the IPv4 address in dotted decimal notation.

Secondary IP Address

Secondary IPv4 address in dotted decimal notation. You can configure multiple secondary addresses for an interface.

Secondary NetMask

Network mask for the secondary IPv4 address in dotted decimal notation.

Helper IP Address

DHCP Helper address used to enable the forwarding of User Datagram Protocol (UDP) broadcasts.

IPv6 Address Settings

Primary/Prefix-length

IPv6 prefix in an x:x:x::x/length format.

EUI64

IPv6 address that is in the extended universal identifier (EUI)-64 format.

Link Local

IPv6 link local address in an x:x:x::x format.

Use local only

Link local address overrides automatically generated IPv6 address.

Secondary IP Address/Prefix Length

Secondary IPv6 prefix in an x:x:x::x/length format.You can configure multiple secondary addresses for an interface.

EUI64

Secondary IPv6 address that is in the extended universal identifier (EUI)-64 format.


Loopback: Statistics Tab

Table 4-3 Loopback: Statistics Tab 

Field
Description

Status

Status of statistics collection. Roll over Status to get a popup tip.

Select Parameters

List of statistics that can be gathered on loopback interfaces.

Show Overview Chart

Overview pop-up of statistics.


VLAN Network Interface

This section includes the following field descriptions for VLAN network interfaces:

VLAN Network Interface: Details Tab: Basic Settings Section

VLAN Network Interface: Details Tab: IP Address Settings Section

VLAN Network Interface: Statistics Tab

VLAN Network Interface: Details Tab: Basic Settings Section

Table 4-4 VLAN Network Interface: Details: Basic Settings 

Field
Description

Name

Display only. Name of the VLAN network interface.

Admin Status

Administrative status of the VLAN network interface. the default is up.

MTU (bytes)

Maximum Transmission Unit. The default is 1500.

Description

String that describes the VLAN network interface.

Delay (tens of usecs)

Interface throughput delay, in tens of microseconds. The default is 1 (10 microseconds).

Oper Status

Carrier delay timer in seconds or milliseconds. The default is 2 seconds.

Carrier Delay

Operational status of the VLAN network interface.

Bandwidth (kb)

Interface bandwidth of the VLAN network interface in kilobytes. The default is 100000.


VLAN Network Interface: Details Tab: IP Address Settings Section

Table 4-5 VLAN Network Interface: Details: IP Address Settings 

Field
Description
IPv4 Address Settings

Primary

IPv4 Address, in dotted decimal notation.

Net mask

Network mask for the IPv4 address in dotted decimal notation.

Secondary IP Address

Secondary IPv4 Address, in dotted decimal notation. You can configure multiple secondary addresses for an interface.

Secondary NetMask

Network mask for the secondary IPv4 address in dotted decimal notation.

Helper IP Address

Helper address used to enable the forwarding of User Datagram Protocol (UDP) broadcasts.

IPv6Address Settings

Primary/Prefix-length

IPv6 prefix in x:x:x::x/length format.

EUI64

IPv6 address that is in the extended universal identifier (EUI)-64 format.

Link Local

IPv6 link local address in an x:x:x::x format.

Use local only

Link local address that overrides automatically generated IPv6 address.

Secondary IP Address/Prefix Length

Secondary IPv6 prefix in an x:x:x::x/length format. You can configure multiple secondary addresses for an interface.

EUI64

Secondary IPv6 address that is in the extended universal identifier (EUI)-64 format.


VLAN Network Interface: Statistics Tab

Table 4-6 VLAN Network Interface: Statistics Tab 

Field
Description

Status

Status of statistics collection. Roll over Status to get a popup tip.

Select Parameters

List of statistics that can be gathered on VLAN network interfaces.

Show Overview Chart

Overview pop-up of statistics.


Additional References

For additional information related to implementing Layer 3 interfaces, see the following sections:

Related Documents

MIBs

Standards

Related Documents

Related Topic
Document Title

command syntax

Cisco Nexus 7000 Series NX-OS Interfaces Command Reference

IP

"Configuring IP" chapter in the Unicast Configuration Guide, Cisco DCNM for LAN, Release 5.x

VLANs

"Configuring VLANs" chapter in the Layer 2 Switching Configuration Guide, Cisco DCNM for LAN, Release 5.x


MIBs

MIBs
MIBs Link

IF-MIB

CISCO-IF-EXTENSION-MIB

ETHERLIKE-MIB

To locate and download MIBs, go to the following URL:

http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml


Standards

Standards
Title

No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.


Feature History for Configuring Layer 3 Interfaces

Table 4-7 lists the release history for this feature.

Table 4-7 Feature History for Configuring Layer 3 Interfaces 

Feature Name
Releases
Feature Information

Layer 3 interfaces

4.0(1)

This feature was introduced.

SVI

4.0(3)

Changed to VLAN Network Interface on entire DCNM and all documentation.