Cisco Nexus 7000 Series NX-OS FabricPath Configuration Guide
FabricPath Switching
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Table Of Contents

Configuring FabricPath Switching

Information About FabricPath Switching

FabricPath Encapsulation

FabricPath Headers

Forwarding Tags (FTags)

Default IS-IS Behavior with FabricPath

Conversational MAC Address Learning

Core Port Learning

Switching Using FabricPath

FEX Support for an Emulated Switch

Conflict Resolution and Optional FabricPath Tunings

Interoperation Between the M Series and the F Series Modules

High Availability

Virtual Device Contexts

Licensing Requirements for FabricPath Switching

Prerequisites for FabricPath Switching

Guidelines and Limitations for FabricPath Switching

Default Settings

Configuring FabricPath Switching

Enabling the FabricPath Feature Set on the VDC on the Device

Disabling the FabricPath Feature Set on the VDC

Configuring the MAC Learning Mode for CE VLANs (Optional)

Configuring the Remote MAC Learning Mode (Optional)

Configuring the MAC Learning Mode for Core Ports (Optional)

Configuring the Switch ID (Optional)

Configuring the FabricPath Timers (Optional)

Disabling FabricPath Graceful Merges (Optional)

Configuring TTL for Unicast and Multicast Packets (Optional)

Forcing the Links to Come Up (Optional)

Verifying FabricPath Switching

Monitoring and Clearing FabricPath Switching Statistics

Configuration Example for FabricPath Switching

Feature History for Configuring FabricPath Switching Using the CLI


Configuring FabricPath Switching



Note You must have an F Series module installed in your Cisco Nexus 7000 Series chassis in order to run FabricPath and conversational learning.


This chapter describes how to configure FabricPath switching on the Cisco NX-OS devices.

This chapter includes the following sections:

Information About FabricPath Switching

Licensing Requirements for FabricPath Switching

Prerequisites for FabricPath Switching

Guidelines and Limitations for FabricPath Switching

Configuring FabricPath Switching

Verifying FabricPath Switching

Monitoring and Clearing FabricPath Switching Statistics

Configuration Example for FabricPath Switching

Feature History for Configuring FabricPath Switching Using the CLI

Information About FabricPath Switching

FabricPath switching allows multipath networking at the Layer 2 level. The FabricPath network still delivers packets on a best-effort basis (which is similar to the Classical Ethernet [CE] network), but the FabricPath network can use multiple paths for Layer 2 traffic. In a FabricPath network, you do not need to run the Spanning Tree Protocol (STP) with its blocking ports. Instead, you can use FabricPath across data centers, some of which have only Layer 2 connectivity, with no need for Layer 3 connectivity and IP configurations.

The FabricPath encapsulation facilitates MAC mobility and server virtualization, which means that you can physically move the Layer 2 node but retain the same MAC address and VLAN association for the virtual machine. FabricPath also allows LAN extensions across data centers at Layer 2, which is useful in disaster recovery operations, as well as clustering applications such as databases. Finally, FabricPath is very useful in high-performance, low-latency computing.

With FabricPath, you use the Layer 2 intermediate System-to-Intermediate System (IS-IS) protocol for a single control plane that functions for unicast, broadcast, and multicast packets. There is no need to run the Spanning Tree Protocol (STP); it is a purely Layer 2 domain. This FabricPath Layer 2 IS-IS is a separate process than Layer 3 IS-IS.

Beginning in the Cisco NX-OS Release 5.1 and when you use the F Series module, Cisco supports the conversation-based MAC learning schema. Conversational learning can be applied to both FabricPath (FP) and CE VLANs. Using FabricPath and conversational MAC address learning, the device has to learn far fewer MAC addresses, which results in smaller, more manageable MAC tables.

This section includes the following topics:

FabricPath Encapsulation

Default IS-IS Behavior with FabricPath

Conversational MAC Address Learning

Switching Using FabricPath

Conflict Resolution and Optional FabricPath Tunings

Interoperation Between the M Series and the F Series Modules

High Availability

Virtual Device Contexts

FabricPath Encapsulation

This section includes the following topics:

FabricPath Headers

Forwarding Tags (FTags)

FabricPath Headers

When a frame enters the FabricPath network, the system encapsulates the Layer 2 frame with a new FabricPath header. The switch IDs that the system assigns to each FabricPath device as it enters the FabricPath network is used as the outer MAC destination address (ODA) and outer MAC source address (OSA) in the FabricPath header. Figure 2-1 shows the FabricPath header encapsulating the classical Ethernet (CE) frame.

Figure 2-1 FabricPath Frame Encapsulation

The system applies the encapsulation on the ingressing edge port of the FabricPath network and decapsulates the frame on the egressing edge port of the FabricPath network; all the ports within the FabricPath network are FabricPath ports that use only the hierarchical MAC address (see Chapter 3 "Configuring FabricPath Interfaces," for more information on configuring FabricPath interfaces). This feature greatly reduces the size of the MAC tables in the core of the FabricPath network.

The system automatically assigns each device in the FabricPath network with a unique switch ID. Optionally, you can configure the switch ID for the FabricPath device.

The outer source address (OSA) is the FabricPath switch ID of the device where the frame ingresses the FabricPath network, and the outer destination address (ODA) is the FabricPath switch ID of the device where the frame egresses the FabricPath network. When the frame egresses the FabricPath network, the FabricPath device strips the FabricPath header, and the original CE frame continues on the CE network. The FabricPath network uses only the OSA and ODA, with the Layer 2 IS-IS protocol transmitting the topology information. Both the FabricPath ODA and OSA are in a standard MAC format (xxxx.xxxx.xxxx).

The FabricPath hierarchical MAC address carries the reserved EtherType 0x8903.

When the frame is originally encapsulated, the system sets the Time to Live (TTL) to 32. Optionally, you can configure the TTL value for multicast and unicast traffic. On each hop through the FabricPath network, each switch decrements the TTL by 1. If the TTL reaches 0, that frame is discarded. This feature prevents the continuation of any loops that may form in the network.

Forwarding Tags (FTags)

The Forwarding Tag (FTag) in the FabricPath header specifies which one of multiple paths that the packet traverses throughout the FabricPath network. The system uses the FTag-specified paths for multidestination packets that enter the FabricPath network. The FTag is a fixed route that the software learns from the topology. The FTag is a 10-bit field with the values from 1 to 1023 (see Chapter 4 "Configuring FabricPath Forwarding," for more information on topologies and multiple paths).

This FTag is assigned on the edge port as the frame ingresses the FabricPath network and is honored by all subsequent FabricPath switches in that FabricPath network. Each FTag is unique within one FabricPath topology.

Default IS-IS Behavior with FabricPath

The interfaces in a FabricPath network run only the FabricPath Layer 2 IS-IS protocol; you do not need to run STP in the FabricPath network because FabricPath Layer 2 IS-IS discovers topology information dynamically.

FabricPath Layer 2 IS-IS is a dynamic link-state routing protocol that detects changes in the network topology and calculates loop-free paths to other nodes in the network. Each FabricPath device maintains a link-state database (LSDB) that describes the state of the network; each device updates the status of the links that are adjacent to the device. The FabricPath device sends advertisements and updates to the LSDB through all the existing adjacencies. FabricPath Layer 2 IS-IS protocol packets do not conflict with standard Layer 3 IS-IS packets because the FabricPath packets go to a different Layer 2 destination MAC address than that used by standard IS-IS for IPv4/IPv6 address families.

The system sends hello packets on the FabricPath core ports to form adjacencies. After the system forms IS-IS adjacencies, the FabricPath unicast traffic uses the equal-cost multipathing (ECMP) feature of Layer 2 IS-IS to forward traffic, which provides up to 16 paths for unicast traffic.

Within the FabricPath network, you use a single control plane protocol, Layer 2 IS-IS, for all unicast, multicast, and broadcast traffic. To use the basic FabricPath functionality, you do not need to configure Layer 2 IS-IS because you can use the default topology. The control plane Layer 2 IS-IS comes up and runs automatically when you enable FabricPath on the device.

The loop-free Layer 2 IS-IS protocol builds two trees for the topology. One tree carries unknown unicast, broadcast, and multicast traffic, and the second tree carries load-balanced multicast traffic. The system load balances multicast traffic across both trees (see Chapter 4 "Configuring FabricPath Forwarding," for more information about trees and topology).

FabricPath Layer 2 IS-IS is based on the standard IS-IS protocol with the following extensions for the FabricPath environment:

FabricPath has a single IS-IS area with no hierarchical Layer 1/Layer 2 routing as prescribed within the IS-IS standard. All devices within the FabricPath network are in a single Layer 1 area.

Multiple instances of IS-IS can be run, one per set of VLANs/topology.

The system uses a MAC address that is different from the MAC address used for Layer 3 IS-IS instances.

The system adds a new sub-TLV that carries switch ID information, which is not in standard IS-IS. This feature allows Layer 2 information to be exchanged through the existing IS-IS protocol implementation.

Within each FabricPath Layer 2 IS-IS instance, each device computes its shortest path to every other device in the network by using the shortest-path first (SPF) algorithm. This path is used for forwarding unicast FabricPath frames. FabricPath Layer 2 IS-IS uses the standard IS-IS functionality to populate up to 16 routes for a given destination device. The system uses multiple equal-cost available parallel links that provide equal-cost multipathing (ECMP).

FabricPath IS-IS introduces certain modifications to the standard IS-IS in order to support the construction of broadcast and multicast trees (identified by the FTags). Specifically, using FabricPath, the system constructs two loop-free trees for forwarding multidestination traffic.

Once the adjacency is established among the devices in the FabricPath network, the system sends update information to all neighbors.

By default, you can run Layer 2 IS-IS with FabricPath with no configuration, however, you can fine-tune some of the Layer 2 IS-IS parameters (see Chapter 5 "Advanced FabricPath Features," for information about configuring optional IS-IS parameters).

Additionally, FabricPath IS-IS helps to ensure that each switch ID in steady-state is unique within the FabricPath network. If FabricPath networks merge, switch IDs might collide. If the IDs are all dynamically assigned, FabricPath IS-IS ensures that this conflict is resolved without affecting any FabricPath traffic in either network.

Conversational MAC Address Learning


Note You must be working on the F Series module in your Cisco Nexus 7000 Series chassis to use conversational MAC learning.


In traditional MAC address learning, each host learns the MAC address of every other device on the network. When you configure a VLAN for conversational learning, the associated interfaces learn only those MAC addresses that are actively speaking to them. Not all interfaces have to learn all the MAC addresses on an F Series module, which greatly reduces the size of the MAC address tables.

Beginning with Cisco NX-OS Release 5.1 when you use the F Series module, you can optimize the MAC learning process. Conversational MAC learning is configured per VLAN. All FabricPath VLANs always use conversational learning; you can configure CE VLANs for conversational learning on this module also. (See Chapter 4 "Configuring FabricPath Forwarding," for more information about CE and FabricPath VLANs.)

The F Series modules have 16 forwarding engines (FEs), and the MAC learning takes place on only one of these FEs. Each FE performs MAC address learning independently of the other 15 FEs on the module. An interface only maintains a MAC address table for the MACs that ingress or egress through that FE; the interface does not have to maintain the MAC address tables on the other 15 FEs on the module.

Conversational MAC address learning and the 16 forward engines (FEs) on each F Series module result in MAC address tables that are much smaller for FabricPath.

The MAC address learning modes available on the F Series modules are the traditional learning and conversational learning. The learning mode is configurable and is set by VLAN mode.

The following VLAN modes have the following MAC learning modes:

FabricPath (FP) VLANs—Only conversational MAC learning.

CE VLANs—Traditional learning by default; you can configure CE VLANs on the F Series module for conversational learning.

With conversational MAC learning, the interface learns only the source MAC address of an ingressing frame if that interface already has the destination MAC address present in the MAC address table. If the source MAC address interface does not already know the destination MAC address, it does not learn that MAC address. Each interface learns only those MAC addresses that are actively speaking with the interface. In this way, conversational MAC learning consists of a three-way handshake. The interface learns the MAC address only if that interface is having a bidirectional conversation with the corresponding interface. Unknown MAC address are forwarded, or flooded, throughout the network.

This combination of conversational MAC address learning and multiple FEs on each F Series module produces smaller MAC address tables on each F Series module.

For CE VLANs, you can configure conversational learning per VLAN on the F Series module by using the command-line interface (CLI). CE VLANs use traditional MAC address learning by default.Traditional MAC learning is not supported on FabricPath VLANs with Cisco Release NX-OS 5.1 or later releases.

Figure 2-2 shows the allowed FabricPath and CE ports on the M and F Series modules and the allowed FP and CE VLANs.

Figure 2-2 FP and CE VLAN Examples

Core Port Learning

Beginning with Cisco NX-OS Release 6.1, support for a Fabric Extender (FEX) with a virtual port channel + (VPC+) on F2 cards is available. FEX VPCs do not have unique subswitch IDs assigned and use the core port learning mode for forwarding.

With the core port learning mode, all local MACs are copied to the core port forwarding engines (FEs) and the MAC address table for the F2 module displays locally learned MAC addresses that are populated on core ports.

The core port learning mode is enabled by default on F2 VDCs.

Beginning with Cisco NX-OS Release 6.1(2), you can disable MAC address learning on F2 Series modules. All the active or used ports on the port group must be FabricPath core ports.

For VLANs where an SVI exists, the F2 module learns the source MAC addresses from the broadcast frames on the FabricPath core ports, whether the MAC learning is enabled or not.

For any port group with MAC learning disabled, the F2 module does not learn the source MAC addresses from the broadcast frames in all the VLANs to which the port group belongs.

Switching Using FabricPath

The FabricPath hierarchical MAC address scheme and conversational learning result in much smaller, conversational learning MAC tables within the FabricPath network. Within the FabricPath network, the system uses Layer 2 IS-IS to transmit topology information. The interfaces on the edge of the network, which use conversational MAC address learning, do not have to learn all the MAC addresses in the network (see Figure 2-3).

Figure 2-3 FabricPath Ports Use Only the FabricPath Header to Switch Frames

MAC mobility is expedited using the FabricPath hierarchical MAC addresses. That is, when you want to move a host and keep its same MAC address and VLANs, only the interfaces at the edge of the FabricPath network track this change. Within the FabricPath network, the FabricPath interfaces update their tables with only the outer MAC addresses (ODA and OSA) that have changed from the FabricPath encapsulation.

See Chapter 3 "Configuring FabricPath Interfaces," for information about FabricPath interfaces.

The interface on the edge of the FabricPath network encapsulates the original frame inside the FabricPath header. Once the frame reaches the last, or directly connected, FabricPath switch, the egress interface strips the FabricPath header and forwards the frame as a normal CE frame.

The ports on an F Series module at the edge of a FabricPath network can use conversational learning to learn only those MAC addresses that the specified edge port is having a bidirectional conversation with. Every edge interface does not have to learn the MAC address of every other edge interface; it just learns the MAC addresses of the speakers.

As the frame traverses the FabricPath network, all the devices work only with the FabricPath header. So, the FabricPath interfaces work only with the ODAs and OSAs; they do not need to learn the MAC address for any of the CE hosts or other devices attached to the network. The hierarchical MAC addressing provided by the FabricPath headers results in much smaller MAC tables in the FabricPath network, which are proportional to the number of devices in that network. The interfaces in the FabricPath network only need to know how to forward frames to another FabricPath switch so they can forward traffic without requiring large MAC address lookup tables in the core of the network.

The switches in the FabricPath network decrement the TTL in the FabricPath header by 1 at each hop. When the TTL reaches 0, the packet is dropped. This process prevents the continuation of any loops that might form in the network.

FEX Support for an Emulated Switch

Beginning with Cisco NX-OS Release 6.1, support for a FEX with a VPC+ on F2 cards is available. Using VPC+, an emulated switch can be configured using two FEXs.


Note For more information about FEXs, see the Configuring the Cisco Nexus 2000 Series Fabric Extender.


An example topology of two FEXs acting as an emulated switch is shown in Figure 2-4.

Figure 2-4

Two FEXs as an Emulated Switch.


Note All the VPC+s of the same FEX have the same outer source address (OSA).


Because a FEX with VPC+ on F2 cards requires core port learning, the subswitch ID and flood ID fields of the outer source MAC addresses are reserved values and are not used.


Note Core port learning is enabled by default on F2 VDCs.


FEX orphan ports have the outer source MAC address of the physical switch to which it is connected.

Partial Mode for FEX with VPC+

To allow a FEX with a VPC+ to function properly, the switch must operate in a partial FTag pruning mode. Traditionally, VPC+ environments operate in an all or none pruning mode where a physical switch is designated as a primary forwarder. The peer acts as the secondary forwarder if the primary path is down. However, in a FEX with a VPC+ configuration, one switch acts as a designated forwarder for half the available FTags and the other switch forwards the other half. If one of the VPC+ paths is down, the packet is forwarded by the peer switch.


Note To configure the FEX port with VPC+, use the fabricpath multi-cast load balance command.


Configuration Example

This example shows how to configure FEXs with VPC+ for an emulated switch. The following steps must be executed on both VPC peers.

Before you begin the configuration steps, ensure the following:

Enable the FabricPath feature set.

Enable the FEX feature set.

To configure the emulated switch, perform these steps:


Step 1 In the VPC domain configuration mode, enable partial DF mode with the fabricpath multicast load-balance command.

Step 2 In the VPC domain configuration mode, configure the emulated switch ID.

switch# configure terminal
switch(config)# interface port-channel channel-number
switch(config-if)# vpc domain ID
switch(config-vpc-domain)# fabricpath switch-id emulated switch-id

Step 3 Configure a FEX.

switch# configure terminal
switch(config)# interface port-channel channel
switch(config-if)# switchport
switch(config-if)# switchport mode fex-fabric
switch(config-if)# fex associate FEX-number
switch(config-if)# no shutdown
switch(config-if)# exit
switch# show interface port-channel channel fex-intf
 
 

Step 4 Create a FEX Layer 2 host interface (HIF) port channel.

switch# configure terminal
switch(config)# interface ethernet FEX-number/1/satellite_port_numnber
switch(config-if)# Channel-group id/1001
switch(config-if)# no shutdown
 
 

Step 5 Configure the VPC ID on the FEX Layer 2 host interface (HIF) port channel.

switch# configure terminal
switch# interface port-channel 1001
switch(config-if)# switchport
switch(config-if)# vpc vpcid
switch(config-if)# no shutdown

Conflict Resolution and Optional FabricPath Tunings

After you enable FabricPath in all devices, the system automatically assigns a random switch ID to each FabricPath device. The switch ID is a 12-bit value that is dynamically assigned to every switch in the FabricPath network, with each switch being a unique value in that FabricPath network. Optionally, you can configure a specific switch ID. If any of the switch IDs in the FabricPath network are not unique, the system provides automatic conflict resolution.

The FabricPath system chooses a random value for the switch ID and sets this value as tentative during a period when the system waits to hear if this value is already in use. If this value is being used by another device in the network, the system begins a conflict resolution process. The switch with the lower system ID keeps the specified value and the other switch gets a new value for its switch ID.

In the case of a single switch joining an existing FabricPath network, the single switch changes the switch ID value rather than any switches in the existing switches in the network changing values. If the specified value is not in use by another device or after the conflict is resolved, the switch ID is marked as confirmed.

Graceful migration provides that there is no traffic disruption if a conflict arises in the resources, such as two switches that temporarily have the same switch ID.


Note The FabricPath interfaces will come up, but they are not operational until the switch checks for FabricPath conflicts and resolves those conflicts.


The FabricPath resource timers have default values, but you can also change the timer values. You can tune the device to wait longer or shorter periods to check the conflicts.

Some of the important processes of the FabricPath network are as follows:

Achieves a conflict-free allocation of switch IDs and FTags

Provides graceful resource migration during network merges or partition healing

Supports static switch IDs

Provides fast convergence during link bringup or network merge

FabricPath uses the Layer 2 IS-IS protocol to transport the database to all switches in the network. The information is distributed among the FabricPath network devices using an IS-IS TLV. Each switch sends its version of the database that contains information about all the switches.

The system allocates the FabricPath values, guarantees their uniqueness within the FabricPath network, and deletes the value from the database once that resource is no longer needed.


Note When you manually configure static switch IDs for the device, the automatic conflict resolution process does not work and the network does not come up. You will see syslog messages about the conflict and must manually change one or more switch IDs of the devices in the network.


Interoperation Between the M Series and the F Series Modules

Beginning with Cisco NX-OS Release 6.2(2), when you have an M Series module and an F Series module in the same Cisco Nexus 7000 Series chassis, you can see the following:

For an M Series module and an F2e Series module—When talking to the router MAC addresses, MAC address learning occurs on the core ports of the F2e Series modules. This problem is an F2e ASIC limitation and support is provided to disable MAC address learning. See the "Configuring the MAC Learning Mode for Core Ports (Optional)" section. Core and edge ports should not be on the same ASIC or forwarding engine in this scenario because MAC learning is disabled.

For an M Series module and an F2e Series module—To support F1 access switches in ISSU that do not copy local MAC addresses to the core ports, the M Series and F2e Series modules learn all the remote MAC addresses by default. Support is provided to disable remote MAC address learning. See the "Configuring the Remote MAC Learning Mode (Optional)" section. When all the switches in the FabricPath topology are moved to Cisco NX-OS Release 6.2(2), remote MAC address learning can be disabled.

For an M Series module and an F2e Series module—To enable proxy learning for Layer 2 on the M Series module, you must disable MAC address learning on the F2e Series module. See the "Configuring the MAC Learning Mode for Core Ports (Optional)" section. You also must disable remote MAC address learning. See the "Configuring the Remote MAC Learning Mode (Optional)" section.

For an M Series module and an F1 Series module—When talking to all the remote MAC addresses, MAC address learning occurs. After an ISSU to Cisco NX-OS Release 6.2(2) for F1 Series core ports, you can disable remote MAC address learning on the F1 Series core ports. See the "Configuring the Remote MAC Learning Mode (Optional)" section.

Beginning with Cisco NX-OS Release 6.2(2), MAC address learning occurs on M Series module pointing to a gateway port channel (GPC). This scenario occurs in both an M Series module with an F1 Series module and an M Series module with an F2E Series module.

Beginning with Cisco NX-OS Release 6.2(2), when you route using a switch virtual interface (SVI) on an M Series module and that F2e operates in a Layer 2-only mode, the large MAC address table of the M Series module can address up to 128,000 hosts in the FabricPath network.

Beginning with Cisco Release 5.2(1) for the Nexus 7000 Series devices, the MAC learning for the F Series FabricPath-enabled modules when an M Series module is present in the chassis has changed. In this configuration, the FabricPath switches copy all locally learned MAC address entries onto the core port, which is the default learning mode in a chassis that contains both F Series and M Series modules.

When you have an M Series module and an F Series module in the same Cisco Nexus 7000 Series chassis, the FabricPath interface on the F Series modules also learns the MAC addresses that traverse that port from the M Series module. The FabricPath interface provides proxy learning for the MAC addresses on the M Series module in the mixed chassis.

Because M Series modules cannot enable FabricPath, those FabricPath-enabled interfaces that coexist in the same Cisco Nexus 7000 Series chassis do have to learn the MAC addresses of the packets that are traversing the FabricPath-enabled F Series interfaces from the M Series interfaces. The FabricPath interface provides proxy learning for the MAC addresses on the M Series module in the mixed chassis.

See the Cisco Nexus 7000 Series NX-OS Unicast Routing Configuration Guide and the Cisco Nexus 7000 Series NX-OS Multicast Routing Configuration Guide for more information about interoperation between the F1 Series and M Series modules.

High Availability

The FabricPath topologies retain their configuration through an in-service software upgrade (ISSU).

See the Cisco Nexus 7000 Series NX-OS High Availability and Redundancy Guide for more information about high availability.

Virtual Device Contexts

You must install the FabricPath feature set before you enable FabricPath on the switch. See the Configuring Feature Set for FabricPath guide for information on installing the FabricPath feature set.

Because of the multiple FEs on the F Series modules, the following port pairs must be in the same VDC:

Ports 1 and 2

Ports 3 and 4

Ports 5 and 6

Ports 7 and 8

Ports 9 and 10

Ports 11 and 12

Ports 13 and 14

Ports 15 and 16

Ports 17 and 18

Ports 19 and 20

Ports 21 and 22

Ports 23 and 24

Ports 25 and 26

Ports 27 and 28

Ports 29 and 30

Ports 31 and 32

See the Virtual Device Context Configuration Guide, Cisco DCNM for LAN, for more information about VDCs.

Licensing Requirements for FabricPath Switching

The following table shows the licensing requirements for this feature:

Product
License Requirement

Cisco NX-OS

FabricPath requires an Enhanced Layer 2 license. For a complete explanation of the Cisco NX-OS licensing scheme, see the Cisco Nexus 7000 Series Licensing Guide.


Prerequisites for FabricPath Switching

FabricPath switching has the following prerequisites:

You should have a working knowledge of Classical Ethernet Layer 2 functionality.

You must install the FabricPath feature set on the default and nondefault VDC before you enable FabricPath on the switch. See Configuring Feature Set for FabricPath for information about installing the FabricPath feature set.

You are logged onto the device.

Ensure that you have installed the Enhanced Layer 2 license.

You are in the correct virtual device context (VDC). A VDC is a logical representation of a set of system resources. You can use the switchto vdc command with a VDC number.

You are working on the F Series module.

Guidelines and Limitations for FabricPath Switching

FabricPath switching has the following configuration guidelines and limitations:

FabricPath interfaces carry only FabricPath-encapsulated traffic.

You enable FabricPath on each device before you can view or access the commands. Enter the feature-set fabricpath command to enable FabricPath on each device. See Configuring Feature-Set for FabricPath for complete information on installing and enabling the FabricPath feature set.

The FabricPath feature set operation might cause the standby supervisor to reload if it is in an unstable state, such as following a service failure or powering up.

STP does not run inside a FabricPath network.

The F Series modules do not support multiple SPAN destination ports or virtual SPAN. If a port on an F Series module is in a VDC and that VDC has multiple SPAN destination ports, that SPAN session is not brought up.

The following guidelines apply to private VLAN configuration when you are running FabricPath:

All VLANs in a private VLAN must be in the same VLAN mode; either CE or FabricPath. If you attempt to put different types of VLANs into a private VLAN, these VLANs will not be active in the private VLAN. The system remembers the configurations, and if you change the VLAN mode later, that VLAN becomes active in the specified private VLAN.

FabricPath ports cannot be put into a private VLAN.

The system does not support hierarchical static MAC addresses. That is, you cannot configure static FabricPath ODAs or OSAs; you can only configure CE static MAC addresses.

On the F Series modules, user-configured static MAC addresses are programmed on all forwarding engines (FEs) that have ports in that VLAN.

A maximum of 128 switch IDs can be supported in a FabricPath network.

FabricPath does not support VTP when in the same VDC. You must disable VTP when the FabricPath feature set is enabled on the VDC.

Default Settings

Table 2-1 lists the default settings for FabricPath switching parameters.

Table 2-1 Default FabricPath Parameters 

Parameters
Default

FabricPath

Disabled.

MAC address learning mode

FP VLANs—Only conversational learning

CE VLANs—Traditional (nonconversational) learning; can be configured for conversational learning on F Series modules

allocate-delay timer

10 seconds

linkup-delay timer

10 seconds

transition-delay timer

10 seconds

graceful merge

Enabled


Configuring FabricPath Switching

After you enable FabricPath switching on each device, the encapsulation, default IS-IS, and learning occur automatically.


Note You must install the FabricPath feature set before you enable FabricPath on the switch. See Configuring Feature-Set for FabricPath for complete information on installing and enabling the FabricPath feature set.


Instead of using the default values, you can optionally configure the following FabricPath features manually:

The MAC learning mode for Classical Ethernet (CE) VLANs:

Conversational learning is the only MAC learning mode available for FabricPath (FP) VLANs.

Various values that the system uses for conflict resolution and other tunings:

Switch ID for the device that is used globally in the FabricPath network

Timers

Graceful merge of FabricPath networks
(Enabled by default. You might experience traffic drops if the feature is disabled.)

A one-time forcing of the links to come up

This section includes the following topics:

Enabling the FabricPath Feature Set on the VDC on the Device

Disabling the FabricPath Feature Set on the VDC

Configuring the MAC Learning Mode for CE VLANs (Optional)

Configuring the Remote MAC Learning Mode (Optional)

Configuring the MAC Learning Mode for Core Ports (Optional)

Configuring the Switch ID (Optional)

Configuring the FabricPath Timers (Optional)

Disabling FabricPath Graceful Merges (Optional)

Configuring TTL for Unicast and Multicast Packets (Optional)

Forcing the Links to Come Up (Optional)

Enabling the FabricPath Feature Set on the VDC on the Device

You must enable the FabricPath feature set before you can access the commands that you use to configure the feature.


Note You must enable the FabricPath feature set on the default VDC, as well as separately on any other VDCs that are running FabricPath. See Configuring Feature-Set for FabricPath for complete information about installing and enabling the FabricPath feature set.


BEFORE YOU BEGIN

Ensure that you have installed the Enhanced Layer 2 license.

Ensure that you have installed an F Series module.

SUMMARY STEPS

1. configure terminal

2. feature-set fabricpath

3. exit

4. (Optional) show feature-set

5. (Optional) copy running-config startup-config

DETAILED STEPS

 
Command
Purpose

Step 1 

configure terminal

Example:

switch# configure terminal

switch(config)#

Enters global configuration mode.

Step 2 

feature-set fabricpath

Example:

switch(config)# feature-set fabricpath

Enables the FabricPath feature set in the VDC.

Note You must install the FabricPath feature set before you enable FabricPath on the switch. See Configuring Feature-Set for FabricPath for complete information on installing and enabling the FabricPath feature set. Also, you must enable the FabricPath feature set on the default VDC, as well as separately on any other VDCs that are running FabricPath.

Step 3 

exit

Example:

switch(config)# exit

switch#

Exits global configuration mode.

Step 4 

show feature-set

Example:

switch# show feature-set

(Optional) Displays which feature sets are enabled on the device.

Step 5 

copy running-config startup-config

Example:

switch# copy running-config startup-config

(Optional) Copies the running configuration to the startup configuration.

This example shows how to enable the FabricPath feature on the VDC:

switch# configure terminal 
switch(config)# feature-set fabricpath
switch(config)#
 
 

Disabling the FabricPath Feature Set on the VDC


Note When you disable the FabricPath functionality, the device clears all the FabricPath configurations.


When you disable the FabricPath functionality, you will not see any of the CLI commands that you need to configure FabricPath. The system removes all the FabricPath configurations when you disable the feature set.


Note If your FabricPath configuration is large (multiple megabytes in size), disabling the FabricPath functionality may take some time to complete.


BEFORE YOU BEGIN

Ensure that you have installed the Enhanced Layer 2 license.

Ensure that you have installed an F Series module.

SUMMARY STEPS

1. configure terminal

2. no feature-set fabricpath

3. exit

4. (Optional) show feature-set

5. (Optional) copy running-config startup-config

DETAILED STEPS

 
Command
Purpose

Step 1 

configure terminal

Example:

switch# configure terminal

switch(config)#

Enters global configuration mode.

Step 2 

no feature-set fabricpath

Example:

switch(config)# no feature-set fabricpath

Disables the FabricPath feature in the VDC.

Step 3 

exit

Example:

switch(config)# exit

switch#

Exits global configuration mode.

Step 4 

show feature-set

Example:

switch# show feature-set

(Optional) Displays which feature sets are enabled on the device.

Step 5 

copy running-config startup-config

Example:

switch# copy running-config startup-config

(Optional) Copies the running configuration to the startup configuration.

This example shows how to disable the FabricPath feature:

switch# configure terminal 
switch(config)# no feature-set fabricpath
switch(config)#

Configuring the MAC Learning Mode for CE VLANs (Optional)

CE VLANs use traditional learning mode by default. However, you can configure CE VLANs on the F Series modules to use conversational MAC address learning.


Note You cannot configure FP VLANs to use traditional MAC address learning; these VLANs use only conversational learning.


BEFORE YOU BEGIN

Ensure that you have installed the Enhanced Layer 2 license.

Ensure that you have installed an F Series module.

Ensure that you are working with CE VLANs.

SUMMARY STEPS

1. configure terminal

2. mac address-table learning-mode conversational vlan vlan-id

3. exit

4. (Optional) show mac address-table learning-mode {vlan vlan-id}

5. (Optional) copy running-config startup-config

DETAILED STEPS

 
Command
Purpose

Step 1 

configure terminal

Example:

switch# configure terminal

switch(config)#

Enters global configuration mode.

Step 2 

mac address-table learning-mode conversational vlan vlan-id

Example:

switch(config)# mac address-table learning-mode conversational vlan 1-10

switch(config)#

Configures the specified CE VLAN(s) on F Series modules for conversational MAC learning. Enter the no form of the command to return to traditional (or nonconversational learning) MAC learning mode. The default MAC learning mode for CE VLANs is traditional.

Note You cannot configure FP VLANs for the traditional MAC address learning mode.

Step 3 

exit

Example:

switch(config)# exit

switch#

Exits global configuration mode.

Step 4 

show mac address-table learning-mode {vlan vlan-id}

Example:

switch# show mac address-table learning-mode

(Optional) Displays the VLANs and the MAC learning mode.

Step 5 

copy running-config startup-config

Example:

switch# copy running-config startup-config

(Optional) Copies the running configuration to the startup configuration.

This example shows how to configure conversational MAC address learning on specified CE VLANs on the F Series module:

switch# configure terminal 
switch(config)# mac address-table learning-mode conversational vlan 1-10
switch(config)#

Configuring the Remote MAC Learning Mode (Optional)

By default, the MAC address learning mode is enabled. You can disable or enable remote MAC address learning for a mixed chassis that contains an M Series module and an F2e Series module (M-F2e) or an M Series module and an F1 Series module (M-F1).

BEFORE YOU BEGIN

Ensure that you have installed the Enhanced Layer 2 license.

Ensure that you have installed an F Series module.

SUMMARY STEPS

1. configure terminal

2. [no] mac address-table fabricpath remote-learning

3. exit

4. (Optional) show system internal l2fm info detail

5. (Optional) copy running-config startup-config

DETAILED STEPS

 
Command
Purpose

Step 1 

configure terminal

Example:

switch# configure terminal

switch(config)#

Enters global configuration mode.

Step 2 

[no] mac address-table fabricpath remote-learning

Example:

switch(config)# no mac address-table fabricpath remote-learning

Enables the remote MAC address learning mode. To disable the remote MAC address learning mode, enter the no form of this command.

Note Ensure that all active or used ports in the module or port group are core ports.

Step 3 

exit

Example:

switch(config)# exit

switch#

Exits global configuration mode.

Step 4 

show system internal l2fm info detail

Example:

switch# show system internal l2fm info detail

(Optional) Displays the Layer 2 feature manager detailed information.

Step 5 

copy running-config startup-config

Example:

switch# copy running-config startup-config

(Optional) Copies the running configuration to the startup configuration.

This example shows how to enable the MAC address learning mode:

switch# configure terminal 

switch(config)# mac address-table fabricpath remote-learning

 
 

This example shows how to disable the MAC address learning mode:

switch# configure terminal 
switch(config)# no mac address-table fabricpath remote-learning
 
 

Configuring the MAC Learning Mode for Core Ports (Optional)

By default, the MAC address learning mode is enabled. You can disable or enable MAC address learning on F2 modules. You can also disable or enable MAC address learning for a mixed chassis that contains an M Series module and an F2e Series module. The command is available only in the default or admin VDC.

BEFORE YOU BEGIN

Ensure that you have installed the Enhanced Layer 2 license.

Ensure that you have installed an F Series module.

Ensure that you are working in the default VDC.

SUMMARY STEPS

1. configure terminal

2. [no] hardware fabricpath mac-learning module module_number {port-group port_group}

3. exit

4. (Optional) show hardware fabricpath mac-learning module module

5. (Optional) show system internal l2fm info detail

6. (Optional) copy running-config startup-config

DETAILED STEPS

 
Command
Purpose

Step 1 

configure terminal

Example:

switch# configure terminal

switch(config)#

Enters global configuration mode.

Step 2 

[no] hardware fabricpath mac-learning module module_number {port-group port_group}

Example:

switch(config)# hardware fabricpath mac-learning module 2 port-group 1-4

Enables the MAC address learning mode for core ports within the specified module. To disable the MAC address learning mode, enter the no form of this command.

Note Ensure that all active or used ports in the module and port group are core ports.

Step 3 

exit

Example:

switch(config)# exit

switch#

Exits global configuration mode.

Step 4 

show hardware fabricpath mac-learning module module

Example:

switch# show hardware fabricpath mac-learning module 2

(Optional) Displays the module's hardware MAC learning mode.

Step 5 

show system internal l2fm info detail

Example:

switch# show system internal l2fm info detail

(Optional) Displays the Layer 2 feature manager detailed information.

Step 6 

copy running-config startup-config

Example:

switch# copy running-config startup-config

(Optional) Copies the running configuration to the startup configuration.

This example shows how to enable the MAC learning mode for the given port group on the specified module:

switch# configure terminal 

switch(config)# hardware fabricpath mac-learning module 4 port-group 1-4

 
 

This example shows how to disable the MAC learning mode on the specified module:

switch# configure terminal 
switch(config)# no hardware fabricpath mac-learning module 4
 
 

Configuring the Switch ID (Optional)


Note You will not lose any traffic during switch ID changes.


By default, FabricPath assigns each FabricPath device with a unique switch ID after you enable FabricPath on the devices. However, you can manually configure the switch ID.


Note You must make these configurations on each switch that you want to participate in the FabricPath network.


BEFORE YOU BEGIN

Ensure that you are working on an F Series module.

Ensure that you have enabled the FabricPath feature on all devices.

Ensure that you have installed the Enhanced Layer 2 license.

SUMMARY STEPS

1. configure terminal

2. fabricpath switch-id value

3. exit

4. (Optional) show fabricpath switch-id

5. (Optional) copy running-config startup-config

DETAILED STEPS

 
Command
Purpose

Step 1 

configure terminal

Example:

switch# configure terminal

switch(config)#

Enters global configuration mode.

Step 2 

fabricpath switch-id value

Example:

switch(config)# fabricpath switch-id 25

switch(config)#

Specifies the switch ID. The range is from 1 to 4094. There is no default value.

Step 3 

exit

Example:

switch(config)# exit

switch)#

Exits global configuration mode.

Step 4 

show fabricpath switch-id

Example:

switch# show fabricpath switch-id

(Optional) Displays information about the switch IDs.

Step 5 

copy running-config startup-config

Example:

switch# copy running-config startup-config

(Optional) Copies the running configuration to the startup configuration.

This example shows how to manually configure a device to have the FabricPath switch ID of 25:

switch# configure terminal 
switch(config)# fabricpath switch-id 25
switch(config)# 

Configuring the FabricPath Timers (Optional)


Note You must make these configurations on each switch that you want to participate in the FabricPath network.


You can change the following FabricPath timers:

allocate-delay—Configures the delay for a new switch ID to be propagated throughout the network before that value becomes available and permanent.

linkup-delay—Configures the link bringup delay to detect conflicts in the switch ID. If the system does find a conflict, the system takes some time to resolve the conflict and bring FabricPath to an operational state. When redundant links are brought up to connect to known networks, the default behavior is to speed up the link bringup. The timer is not used in this case as the network is already known.

linkup-delay always—Configures the link bringup delay to enfore the timer to be honored in all scenarios.


Note Conflicts that occur with user-configured switch IDs are not resolved. Warning messages are displayed for conflicts of this type. To avoid incorrect traffic forwarding, we recommend that you set the linkup-delay high enough for Intermediate System-to-Intermediate System (IS-IS) to gather neighbor information while changing the topology. A high linkup-delay setting allows the timely detection of conflicts. Links are held down until conflicts are resolved by user intervention or until the expiration of the link-state packet (LSP) of the conflicting switch IDs.

This configuration of timers takes effect only if the link leads to a node that is not yet identified as reachable by the routing protocol. If other equal cost multipaths already exist in the forwarding state and the new link creates another new equal cost multipath, the linkup process might be expedited when the timer configuration is skipped for such links. The timer configuration is used only as a hold time for the routing protocol to gather network information. When networks are known to the routing protocol, you might observe that the timer is not getting used.

For more information about configuring optional IS-IS parameters, see Chapter 5 "Advanced FabricPath Features."


transition-delay—Configures the delay for propagating a transitioned value in the network; during this period, all old and new switch ID values exist in the network. This situation occurs only when the link comes up and the system checks to see if the network has two identical switch IDs.

BEFORE YOU BEGIN

Ensure that you are working on an F Series module.

Ensure that you have enabled the FabricPath feature on all devices.

Ensure that you have installed the Enhanced Layer 2 license.

SUMMARY STEPS

1. configure terminal

2. fabricpath timers {allocate-delay seconds | linkup-delay seconds | linkup-delay always | transition-delay seconds}

3. exit

4. (Optional) show fabricpath timers

5. (Optional) copy running-config startup-config

DETAILED STEPS

 
Command
Purpose

Step 1 

configure terminal

Example:

switch# configure terminal

switch(config)#

Enters global configuration mode.

Step 2 

fabricpath timers {allocate-delay seconds | linkup-delay seconds | linkup-delay always | transition-delay seconds}

Example:

switch(config)# fabricpath timers allocate-delay 600

switch(config)#

Specifies the FabricPath timer values. The range is from 1 to 1200 seconds for each of these timers. The default values are as follows:

allocate-delay—10 seconds

linkup-delay—10 seconds

As a best practice, use a linkup-delay timer value of at least 60 seconds before introducing or joining nodes that are statically configured (directly or indirectly) in the network. This setting avoids incorrect traffic forwarding that might result from conflicts between switch IDs.

linkup-delay always

As a best practice, you should avoid using the linkup-delay always keywords in steady state to speed up link bringups. Use this setting to decrease the traffic loss after you reload modules that provide redundant paths to known networks.

transition-delay—10 seconds

Step 3 

exit

Example:

switch(config)# exit

switch)#

Exits global configuration mode.

Step 4 

show fabricpath timers

Example:

switch# show fabricpath timers

(Optional) Displays information about FabricPath timers.

Step 5 

copy running-config startup-config

Example:

switch# copy running-config startup-config

(Optional) Copies the running configuration to the startup configuration.

This example shows how to configure the allocation-delay FabricPath value to 600 seconds:

switch# configure terminal 
switch(config)# fabricpath timers allocate-delay 600
switch(config)# 

Disabling FabricPath Graceful Merges (Optional)


Note You must make this configuration on each switch that you want to participate in the FabricPath network.


By default, graceful-merge is enabled; you can disable this aspect of the FabricPath feature.


Note You might experience traffic drops if you disable this feature.


BEFORE YOU BEGIN

Ensure that you are working on an F Series module.

Ensure that you have enabled the FabricPath feature on all devices.

Ensure that you have installed the Enhanced Layer 2 license.

SUMMARY STEPS

1. configure terminal

2. [no] fabricpath graceful-merge disable

3. exit

4. (Optional) show running-config

5. (Optional) copy running-config startup-config

DETAILED STEPS

 
Command
Purpose

Step 1 

configure terminal

Example:

switch# configure terminal

switch(config)#

Enters global configuration mode.

Step 2 

[no] fabricpath graceful-merge disable

Example:

switch(config)# fabricpath graceful-merge disable

switch(config)#

Disables graceful merge of the FabricPath feature. To reenable this feature, enter the no form of the command.

Step 3 

exit

Example:

switch(config)# exit

switch)#

Exits global configuration mode.

Step 4 

show running-config

Example:

switch# show running-config

(Optional) Displays information about the configuration running on the switch.

Step 5 

copy running-config startup-config

Example:

switch# copy running-config startup-config

(Optional) Copies the running configuration to the startup configuration.

This example shows how to disable the graceful merge aspect of the FabricPath feature:

switch# configure terminal 
switch(config)# fabricpath graceful-merge disable
switch(config)# 
 
 

Configuring TTL for Unicast and Multicast Packets (Optional)

By default, FabricPath assigns a time to live (TTL) value for unicast and multicast traffic. However, you can overwrite this value.


Note The TTL is applied when the packets ingress on edge ports. The TTL value in the packet is only decremented when the packet travels across core ports.


BEFORE YOU BEGIN

Ensure that you are working on an F Series module.

Ensure that you have enabled the FabricPath feature on all devices.

Ensure that you have installed the Enhanced Layer 2 license.

SUMMARY STEPS

1. configure terminal

2. [no] fabricpath ttl unicast numhops

3. [no] fabricpath ttl multicast numhops

4. exit

5. (Optional) show fabricpath ttl

6. (Optional) copy running-config startup-config

DETAILED STEPS

 
Command
Purpose

Step 1 

configure terminal

Example:

switch# configure terminal

switch(config)#

Enters global configuration mode.

Step 2 

[no] fabricpath ttl unicast numhops

Example:

switch(config)# fabricpath ttl unicast 20

Configures the TTL value for the unicast traffic in the VDC. The range is from 1 to 64 and the default value is 32.

Step 3 

[no] fabricpath ttl multicast numhops

Example:

switch(config)# fabricpath ttl multicast 20

Configures the TTL value for the multicast traffic in the VDC. The range is from 1 to 64 and the default value is 32.

Step 4 

exit

Example:

switch(config)# exit

switch#

Exits global configuration mode.

Step 5 

show fabricpath ttl

Example:

switch# show fabricpath ttl

(Optional) Displays the current TTL configuration for the unicast and multicast traffic.

Step 6 

copy running-config startup-config

Example:

switch# copy running-config startup-config

(Optional) Copies the running configuration to the startup configuration.

This example shows how to configure the TTL values for multicast and unicast traffic:

switch# configure terminal
switch(config)# fabricpath ttl unicast 20
switch(config)# fabricpath ttl multicast 10
switch(config)# exit
switch#
 
 

Forcing the Links to Come Up (Optional)


Note We do NOT recommend that you use the fabricpath force link-bringup command.


As a one-time event, you can force the FabricPath network links to connect if they are not coming up because of switch ID conflicts or other problems in the network.


Note You must make this configuration on each switch that you want to participate in the FabricPath network.



Note This configuration is not saved when you enter the copy running-config startup-config command.


BEFORE YOU BEGIN

Ensure that you are working on an F Series module.

Ensure that you have enabled the FabricPath feature on all devices.

Ensure that you have installed the Enhanced Layer 2 license.

SUMMARY STEPS

1. fabricpath force link-bringup

DETAILED STEPS

 
Command
Purpose

Step 1 

fabricpath force link-bringup

Example:

switch# fabricpath force link-bringup

switch#

Forces the FabricPath network links to come up as a one-time event.

Note This command is not saved when you enter the copy running-config startup-config command.

This example shows how to force the FabricPath network links to come up one time:

switch# fabricpath force link-bringup
switch# 

Verifying FabricPath Switching

To display FabricPath switching information, perform one of the following tasks:

Command
Purpose

show feature-set

Displays whether FabricPath is enabled or not.

show mac address-table learning-mode {vlan vlan-id}

Displays the VLANs and the MAC address learning mode.

Note MAC learning modes are available only on the F Series modules.

show fabricpath conflict {all [detail] | link [detail] | switch-id [detail] | transitions [detail]}

Displays information on conflicts in the FabricPath network.

show fabricpath switch-id [local]

Displays information on the FabricPath network by switch ID.

show fabricpath system-id {mac-addr}

Displays information on the FabricPath network by system ID.

show fabricpath timers

Displays settings for the allocate-delay, linkup-delay, and transition-delay timers for the FabricPath network.


See Chapter 5 "Advanced FabricPath Features," for more commands that display FabricPath switching functionality.

Monitoring and Clearing FabricPath Switching Statistics

Use the following commands to display FabricPath switching statistics:

clear counters [interface]

load- interval {interval seconds {1 | 2 | 3}}

show interface counters [module module]

show interface counters detailed [all]

show interface counters errors [module module]

See the Cisco Nexus 7000 Series NX-OS Interfaces Command Reference for information about these commands.

Configuration Example for FabricPath Switching

After installing the feature set (see Configuring Feature-Set for FabricPath for complete information on installing and enabling the FabricPath feature set), you must enable the FabricPath functionality on all the VDCs that you are using.


Note You must have an F Series module installed in your Cisco Nexus 7000 Series chassis in order to run FabricPath.


To configure FabricPath switching, follow these steps:


Step 1 Enable FabricPath on all the devices.

switch# configure terminal
switch(config)# feature-set fabricpath
switch(config)#
 
 

Step 2 (Optional) Configure MAC address learning mode.

switch(config)# mac address learning-mode conversational vlan 1-10
switch(config)# show mac address-table learning-mode
switch(config)# exit 
 
 

Step 3 (Optional) Manually configure a switch ID for the FabricPath device.

switch# configure terminal
switch(config)# fabricpath switch-id 25
switch(config)# 
 
 

Step 4 Save the configuration.

switch(config)# save running-config startup-config
switch(config)#

Feature History for Configuring FabricPath Switching Using the CLI

Table 2-2 lists the release history for this feature.

Table 2-2 Feature History for FabricPath Switching 

Feature Name
Releases
Feature Information

Proxy Layer 2 learning

6.2(2)

Ability to disable MAC address learning.

MAC Proxy

6.2(2)

Added support for leveraging the MAC address table of an M Series module in order to address up to 128,000 hosts in the FabricPath network.

FabricPath timers

6.2(2)

Linkup-delay always option introduced.

TTL for unicast and multicast packets

6.2(2)

This feature was introduced.

Core port learning

6.1(1)

This feature was introduced.

New default MAC address learning mode in chassis containing both F Series and M Series modules

5.2(1)

This feature was introduced.

FabricPath

5.1(1)

These features were introduced.