MPLS Traffic Engineering (TE) - Class-based Tunnel Selection
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MPLS Traffic Engineering : Class-based Tunnel Selection

Table Of Contents

MPLS Traffic Engineering : Class-based Tunnel Selection

Contents

Prerequisites for MPLS Traffic Engineering : Class-based Tunnel Selection

Restrictions for MPLS Traffic Engineering : Class-based Tunnel Selection

Information About MPLS Traffic Engineering : Class-based Tunnel Selection

Incoming Traffic Supported by MPLS TE Class-based Tunnel Selection

CoS Attributes for MPLS TE Class-based Tunnel Selection

Routing Protocols and MPLS TE Class-based Tunnel Selection

Tunnel Selection with MPLS TE Class-based Tunnel Selection

EXP Mapping Configuration

Tunnel Selection for EXP Values

Tunnel Failure Handling

Misordering of Packets

Fast Reroute and MPLS TE Class-based Tunnel Selection

DS-TE Tunnels and MPLS TE Class-based Tunnel Selection

Reoptimization and MPLS TE Class-based Tunnel Selection

Interarea and Inter-AS and MPLS TE Class-based Tunnel Selection

ATM PVCs and MPLS TE Class-based Tunnel Selection

How to Configure MPLS Traffic Engineering : Class-based Tunnel Selection

Creating Multiple MPLS TE or DS-TE Tunnels from the Same Headend to the Same Tailend

Configuring EXP Values to Be Carried by Each MPLS TE or DS-TE Tunnel

Making the MPLS TE or DS-TE Tunnels Visible for Routing

Verifying That the MPLS TE or DS-TE Tunnels Are Operating and Announced to the IGP

Configuring a Master Tunnel

Configuration Examples for MPLS Traffic Engineering : Class-based Tunnel Selection

Creating Multiple MPLS TE or DS-TE Tunnels from the Same Headend to the Same Tailend: Example

Configuring EXP Values to Be Carried by Each MPLS TE or DS-TE Tunnel: Example

Making the MPLS TE or DS-TE Tunnels Visible for Routing: Example

Verifying That the MPLS TE or DS-TE Tunnels Are Operating and Announced to the IGP: Example

Configuring a Master Tunnel: Example

Additional References

Related Documents

Standards

MIBs

RFCs

Technical Assistance

Feature Information for MPLS Traffic Engineering : Class-based Tunnel Selection

Glossary


MPLS Traffic Engineering : Class-based Tunnel Selection


First Published: November 1, 2003
Last Updated: May 9, 2008

The MPLS Traffic Engineering (TE): Class-based Tunnel Selection feature enables you to dynamically route and forward traffic with different class of service (CoS) values onto different TE tunnels between the same tunnel headend and the same tailend. The TE tunnels can be regular TE or DiffServ-aware TE (DS-TE) tunnels.

The set of TE (or DS-TE) tunnels from the same headend to the same tailend that you configure to carry different CoS values is referred to as a "tunnel bundle." After configuration, Class-Based Tunnel Selection (CBTS) dynamically routes and forwards each packet into the tunnel that:

Is configured to carry the CoS of the packet

Has the right headend for the destination of the packet

Because CBTS offers dynamic routing over DS-TE tunnels and requires minimum configuration, it greatly eases deployment of DS-TE in large-scale networks.

CBTS can distribute all CoS values on eight different tunnels.

CBTS also allows the TE tunnels of a tunnel bundle to exit headend routers through different interfaces.

Finding Feature Information in This Module

Your Cisco IOS software release may not support all of the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release. To reach links to specific feature documentation in this module and to see a list of the releases in which each feature is supported, use the "Feature Information for MPLS Traffic Engineering : Class-based Tunnel Selection" section.

Finding Support Information for Platforms and Cisco IOS and Catalyst OS Software Images

Use Cisco Feature Navigator to find information about platform support and Cisco IOS and Catalyst OS software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.

Contents

Prerequisites for MPLS Traffic Engineering : Class-based Tunnel Selection

Restrictions for MPLS Traffic Engineering : Class-based Tunnel Selection

Information About MPLS Traffic Engineering : Class-based Tunnel Selection

How to Configure MPLS Traffic Engineering : Class-based Tunnel Selection

Configuration Examples for MPLS Traffic Engineering : Class-based Tunnel Selection

Additional References

Command Reference, page 29

Feature Information for MPLS Traffic Engineering : Class-based Tunnel Selection

Glossary

Prerequisites for MPLS Traffic Engineering : Class-based Tunnel Selection

Multiprotocol Label Switching (MPLS) must be enabled on all tunnel interfaces.

Cisco Express Forwarding or distributed Cisco Express Forwarding must be enabled in global configuration mode.

Restrictions for MPLS Traffic Engineering : Class-based Tunnel Selection

For a given destination, all CoS values are carried in tunnels terminating at the same tailend. Either all CoS values are carried in tunnels or no values are carried in tunnels. In other words, for a given destination, you cannot map some CoS values in a DS-TE tunnel and other CoS values in a Shortest Path First (SPF) Label Distribution Protocol (LDP) or SPF IP path.

CBTS does not allow load-balancing of a given experimental (EXP) value in multiple tunnels. If two or more tunnels are configured to carry a given EXP value, CBTS picks one of those tunnels to carry this EXP value.

The operation of CBTS is not supported with Any Transport over MPLS (AToM), MPLS TE Automesh, or label-controlled (LC)-ATM.

Information About MPLS Traffic Engineering : Class-based Tunnel Selection

Incoming Traffic Supported by MPLS TE Class-based Tunnel Selection

CoS Attributes for MPLS TE Class-based Tunnel Selection

Routing Protocols and MPLS TE Class-based Tunnel Selection

Tunnel Selection with MPLS TE Class-based Tunnel Selection

DS-TE Tunnels and MPLS TE Class-based Tunnel Selection

Reoptimization and MPLS TE Class-based Tunnel Selection

Interarea and Inter-AS and MPLS TE Class-based Tunnel Selection

ATM PVCs and MPLS TE Class-based Tunnel Selection

Incoming Traffic Supported by MPLS TE Class-based Tunnel Selection

The CBTS feature supports the following kinds of incoming packets:

At a provider edge (PE) router—Unlabeled packets that enter a Virtual Private Network (VPN) routing and forwarding (VRF) instance interface

At a provider core (P) router—Unlabeled and MPLS-labeled packets that enter a non-VRF interface

At a PE router in a Carrier Supporting Carrier (CSC) or interautonomous system (Inter-AS)—MPLS-labeled packets that enter a VRF interface

CoS Attributes for MPLS TE Class-based Tunnel Selection

CBTS supports tunnel selection based on the value of the EXP field that the headend router imposes on the packet. Before imposing this value, the router considers the input modular quality of service (QoS) command-line interface (CLI) (MQC). If the input MQC modifies the EXP field value, CBTS uses the modified value for its tunnel selection.

Packets may enter the headend from multiple incoming interfaces. These interfaces can come from different customers that have different DiffServ policies. In such cases, service providers generally use input MQC to apply their own DiffServ policies and mark imposed EXP values accordingly. Thus, CBTS can operate consistently for all customers by considering the EXP values marked by the service provider.


Note If the output MQC modifies the EXP field, CBTS ignores the change in the EXP value.


CBTS allows up to eight different tunnels on which it can distribute all classes of service.

Routing Protocols and MPLS TE Class-based Tunnel Selection

CBTS routes and forwards packets to MPLS TE tunnels for specified destinations through use of the following routing protocols:

Intermediate System-to-Intermediate System (IS-IS) with Autoroute configured

Open Shortest Path First (OSPF) with Autoroute configured

Static routing

Border Gateway Protocol (BGP) with recursion configured on the BGP next hop with packets forwarded on the tunnel through the use of IS-IS, OSPF, or static routing

Tunnel Selection with MPLS TE Class-based Tunnel Selection

This section contains the following topics related to tunnel selection:

EXP Mapping Configuration

Tunnel Selection for EXP Values

Tunnel Failure Handling

Misordering of Packets

EXP Mapping Configuration

With CBTS, you can configure each tunnel with any of the following:

The same EXP information configured as it was before the CBTS feature was introduced, that is, with no EXP-related information

One or more EXP values for the tunnel to carry

A property that allows the carrying of all EXP values not currently allocated to any up-tunnel (default)

One or more EXP values for the tunnel to carry, and the default property that allows the carrying of all EXP values not currently allocated to any up-tunnel

The default property (the carrying of all EXP values not currently allocated to any up-tunnel) effectively provides a way for the operator to avoid explicitly listing all possible EXP values. Even more important, the default property allows the operator to indicate tunnel preferences onto which to "bump" certain EXP values, should the tunnel carrying those EXP values go down. (See the tunnel mpls traffic-eng exp command for the command syntax.)

The configuration of each tunnel is independent of the configuration of any other tunnel. CBTS does not attempt to perform any consistency check for EXP configuration.

This feature allows configurations where:

Not all EXP values are explicitly allocated to tunnels.

Multiple tunnels have the default property.

Some tunnels have EXP values configured and others do not have any values configured.

A given EXP value is configured on multiple tunnels.

Tunnel Selection for EXP Values

Tunnel selection with this feature is a two-step process:

1. For a given prefix, routing (autoroute, static routes) occurs exactly as it did without the CBTS feature. The router selects the set of operating tunnels that have the best metrics, regardless of the EXP-related information configured on the tunnel.

2. CBTS maps all of the EXP values to the selected set of tunnels:

If a given EXP value is configured:

On only one of the tunnels in the selected set, CBTS maps the EXP value onto that tunnel.

On two or more of the tunnels in the selected set, CBTS arbitrarily maps the EXP value onto one of these tunnels. First CBTS selects the tunnel on which the lowest EXP value is explicitly configured. Then CBTS picks the tunnel that has the lowest tunnel ID.

If a given EXP value is not configured on any of the tunnels in the selected set:

And only one of the tunnels in the selected set is configured as a default, CBTS maps the EXP value onto that tunnel.

And two or more of the tunnels in the selected set are configured as defaults, CBTS arbitrarily maps the EXP value onto one of these tunnels.

And no tunnel in the selected set of tunnels is configured as a default, CBTS does not map this EXP value onto any specific tunnel. Instead, CBTS performs CoS-unaware load balancing of that EXP information across all tunnels in the selected set.

CBTS relies on autoroute to select the tunnel bundle. Autoroute selects only tunnels that are on the SPF to the destination. Therefore, similar to Autoroute, CBTS does not introduce any risk of routing loops.

Tunnel Selection Examples

The following examples show various tunnel configurations that are set up by an operator and indicate how CBTS maps packets carrying EXP values onto these tunnels. Each example describes a different configuration: a default tunnel configured, more than one tunnel configured with the same EXP value, and so on.

Example 1—Default Tunnel Configured

An operator configures the following parameters on tunnels T1 and T2:

T1: exp = 5, autoroute

T2: exp = default, autoroute

If T1 and T2 are next-hop interfaces for prefix P, CBTS maps the packets onto the tunnels in this way:

Packets with <Dest = P, exp = 5> onto T1

Packets with <Dest = P, exp = anything-other-than-5> onto T2

Example 2— EXP Values Configured on Two Tunnels; One Default Tunnel

An operator configures the following parameters on tunnels T1, T2, and T3:

T1: exp = 5, autoroute

T2: exp = 3 and 4, autoroute

T3: exp = default, autoroute

If T1, T2, and T3 are next-hop interfaces for prefix P, CBTS maps the packets onto the tunnels in this way:

Packets with <Dest = P, exp = 5> onto T1

Packets with <Dest = P, exp = 3 or 4> onto T2

Packets with <Dest = P, exp = 0, 1, 2, 6, or 7> onto T3

Example 3—More than One Tunnel with the Same EXP

An operator configures the following parameters on tunnels T1, T2, and T3:

T1: exp = 5, autoroute

T2: exp = 5, autoroute

T3: exp = default, autoroute

If T1, T2, and T3 are next-hop interfaces for prefix P, CBTS maps the packets onto the tunnels in this way:

Packets with <Dest = P, exp = 5> onto T1 (arbitrary selection)

Packets with <Dest = P, exp = anything-other-than-5> onto T3

No packets onto T2

Example 4—Static Route Configured

An operator configures the following parameters on tunnels T1 and T2:

T1: exp = 5, autoroute

T2: exp = 3

Static route to P on T2

If prefix P is behind the T1 and T2 tailend router, CBTS maps the packets onto the tunnels in this way:

Packets with <Dest = P, exp = anything> onto T2

No packets onto T1

Static routes are preferred over dynamic routes; therefore, the router chooses only T2 as the "selected set" of tunnels.

Example 5—Metrics Configured on Tunnels

An operator configures the following parameters on tunnels T1 and T2:

T1: exp = 5, autoroute, relative metric -2

T2: exp = 3, autoroute, relative metric -3

CBTS maps the packets onto the tunnels in this way:

Packets with <Dest = P, exp = anything> onto T2

No packets onto T1

The autoroute tunnel selection algorithm selects the tunnel with the best metric. Therefore, the router selects only T2 as the "selected set" of tunnels.

Example 6—No Default or Metric Configuration

An operator configures the following parameters on tunnels T1 and T2:

T1: exp = 5, autoroute

T2: exp = 3, autoroute

If T1 and T2 are the next-hop interfaces for prefix P, CBTS maps the packets onto the tunnels in this way:

Packets with <Dest = P, exp = 5> onto T1

Packets with <Dest = P, exp = 3> onto T2

Packets with <Dest = P, exp = anything-other-than-3-or-5> onto T2

If a packet arrives with an EXP value that is different from any value configured for a tunnel, the packet goes in to the default tunnel. If no default tunnel is configured, the packet goes in to the tunnel that is configured with the lowest EXP value.

Multipath with Non-TE Paths and MPLS TE Class-Based Tunnel Selection

For a given prefix in the routing process, the router might select a set of paths that includes both TE tunnels and non-TE-tunnel paths (SPF paths). For example, internal Border Gateway Protocol (iBGP) Multipath might be activated and result in multiple BGP next hops for that prefix, where one BGP next hop is reachable through TE tunnels and other BGP next hops are reachable through non-TE-tunnel paths.

An equal cost IGP path might also exist over TE tunnels and over a non-TE tunnel path. For example, a TE tunnel metric might be modified to be equal to the SPF path.

In these situations, CBTS maps traffic in the following manner:

If a given EXP value is configured on one or more of the tunnels in the selected set, CBTS maps the EXP value onto that tunnel or one of those tunnels.

If a given EXP value is not configured on any of the tunnels in the selected set but one or more of the tunnels is configured as a default in the selected set, then CBTS maps the EXP value onto that tunnel or one of those tunnels.

If a given EXP value is not configured on any of the tunnels from the selected set and no tunnel in the selected set is configured as a default, CBTS performs CoS-unaware load-balancing of that EXP value across all the possible paths, including all of the TE tunnels of the selected set and the non-TE paths.

If the routing process allocates all EXP values to tunnels or if a default is used, then routing does not use the non-TE paths unless all TE tunnels are down.

MPLS TE Class-Based Tunnel Selection and Policy-Based Routing

If you configure both policy-based routing (PBR) over TE tunnels (in non-VRF environments) and CBTS, the PBR decision overrides the CBTS decision. PBR is an input process that the router performs ahead of regular forwarding.

Tunnel Failure Handling

For CBTS operation, the important question is whether the tunnel interface is up or down, not whether the current TE label switched path (LSP) is up or down. For example, a TE LSP might go down but is reestablished by the headend because another path option exists. The tunnel interface does not go down during the transient period while the TE LSP is reestablished. Because the tunnel interface does not go down, the corresponding EXP does not get rerouted onto another tunnel during the transient period.

When a tunnel used by CBTS for forwarding goes down, the feature adjusts its tunnel selection for the affected EXP values. It reapplies the tunnel selection algorithm to define the behavior of packets for all EXP values, as shown in the examples that follow.

Example 1—Tunnel Other than the Default Tunnel Goes Down

An operator configures the following parameters on tunnels T1, T2, and T3:

T1: exp = 5, autoroute

T2: exp = 3 and 4, autoroute

T3: exp = default, autoroute

If T1, T2, and T3 are next-hop interfaces for prefix P and Tunnel T1 goes down, CBTS maps the packets onto the tunnels in this way:

Packets with <Dest = P, exp = 3, 4> onto T2 (as before)

Packets with <Dest = P, exp = 0, 1, 2, 6, or 7> onto T3 (as before)

Packets with <Dest = P, exp = 5> onto T3

Example 2—Default Tunnel Goes Down

An operator configures the following parameters on tunnels T1, T2, and T3:

T1: exp = 5, autoroute

T2: exp = 3 and 4, autoroute

T3: exp = default, autoroute

If T1, T2, and T3 are next-hop interfaces for prefix P and Tunnel T3 goes down, CBTS maps the packets onto the tunnels in this way:

Packets with <Dest = P, exp = 5> onto T1 (as before)

Packets with <Dest = P, exp = 3, 4> onto T2 (as before)

Packets with <Dest = P, exp = 0, 1, 2, 6, or 7> onto T1 and T2, following existing CoS-unaware load balancing

Example 3—Two Default Tunnels Are Configured

An operator configures the following parameters on tunnels T1, T2, and T3:

T1: exp = 5, autoroute

T2: exp = 3, 4, and default, autoroute

T3: exp = 0, 1, 2, 6, 7, and default, autoroute

If T1, T2, and T3 are next-hop interfaces for prefix P and Tunnel T3 goes down, CBTS maps the packets onto the tunnels in this way:

Packets with <Dest = P, exp = 5> onto T1 (as before)

Packets with <Dest = P, exp = 3, 4> onto T2 (as before)

Packets with <Dest = P, exp = 0, 1, 2, 6, or 7> onto T2

If tunnel T2 goes down, CBTS maps the packets onto the tunnels in this way:

Packets with <Dest = P, exp = 5> onto T1 (as before)

Packets with <Dest = P, exp = 0, 1, 2, 6, or 7> onto T3 (as before)

Packets with <Dest = P, exp = 3, or 4> onto T3

If tunnel T1 goes down, CBTS maps the packets onto the tunnels in this way:

Packets with <Dest = P, exp = 3, or 4> onto T2 (as before)

Packets with <Dest = P, exp = 0, 1, 2, 6, or 7> onto T3 (as before)

Packets with <Dest = P, exp = 5> onto either T2 or T3, but not both

In Example 3, the operator configures the EXP default option on two tunnels to ensure that nonvoice traffic is never redirected onto the voice tunnel (T1).

Misordering of Packets

In DiffServ, packets from a given flow might get marked with EXP values that are different from each other but belong to the same CoS value because of in-contract and out-of-contract marking of packets. We can refer to these values of EXP bits as EXP-in and EXP-out.

If packets for EXP-in are sent on a different tunnel than packets for EXP-out, then misordering of packets within the same flows could occur. For that reason, CBTS allows operators to ensure that EXP-in and EXP-out never get mapped onto different tunnels.

The CBTS feature allows the operator to configure EXP-in and EXP-out to be transported on the same tunnel when that tunnel is up. This ensures that the feature does not introduce misordering of packets. In case of tunnel failure, the tunnel selection algorithm ensures that if EXP-in and EXP-out were carried on the same tunnel before the failure, they are still carried on a single tunnel after the failure. Thus, CBTS protects against nontransient misordering even in the event of tunnel failure.


Note CBTS does not attempt to force EXP-in and EXP-out to be carried on the same tunnel. The operator must configure CBTS so that EXP-in and EXP-out are carried on the same tunnel. This is comparable to the regular DiffServ situation, where the operator must ensure that EXP-in and EXP-out are configured to go in the same queue.


Fast Reroute and MPLS TE Class-based Tunnel Selection

CBTS allows Fast Reroute (FRR) protection on tunnels for which you configure CoS-based selection.

CBTS operation with FRR does not change the number of or the way in which FRR backup tunnels might be used. The operation of FFR is the same as when CBTS is not activated. After you configure primary tunnels from a given headend to a given tailend, you can use FRR in the same way whether you activate CoS-based tunnel selection or not. This includes the following possibilities:

None of the tunnels use FRR.

All of the x tunnels are FRR-protected and share the same backup tunnel, if the traffic goes out the same interface.

Some of the x tunnels are not FRR-protected; the remaining tunnels are FRR-protected and share the same backup tunnel, if the traffic goes out the same interface.

Some of the x tunnels are not FRR-protected; the remaining tunnels are FRR-protected and are protected by different backup tunnels (for example, if the traffic goes out different interfaces, or if the traffic goes out the same interface). Bandwidth guarantees exist on the backup tunnels.

The important question for CBTS operation is only whether a tunnel interface goes down or stays up. FRR protects a given tunnel in exactly the same way as if CBTS were not configured on the tunnel.

DS-TE Tunnels and MPLS TE Class-based Tunnel Selection

CBTS operates over tunnels using DS-TE. Therefore, the tunnels on which CoS-based selection is performed can each arbitrarily and independently use a bandwidth from the global pool or the subpool.

Reoptimization and MPLS TE Class-based Tunnel Selection

CBTS allows tunnels on which CoS-based selection is performed to be reoptimized. Reoptimization does not affect CBTS operation.

Interarea and Inter-AS and MPLS TE Class-based Tunnel Selection

The CBTS operates over tunnels that are interarea when the interarea tunnels use static routes on destination prefixes or on the BGP next hops.

ATM PVCs and MPLS TE Class-based Tunnel Selection

CBTS operates over ATM permanent virtual circuits (PVCs). This means that TE or DS-TE tunnels handled by CBTS can span links that are ATM PVCs. ATM PVCs might be used on the headend router that is running CBTS and on transit label switch routers (LSRs).

How to Configure MPLS Traffic Engineering : Class-based Tunnel Selection

Creating Multiple MPLS TE or DS-TE Tunnels from the Same Headend to the Same Tailend

Configuring EXP Values to Be Carried by Each MPLS TE or DS-TE Tunnel

Making the MPLS TE or DS-TE Tunnels Visible for Routing

Verifying That the MPLS TE or DS-TE Tunnels Are Operating and Announced to the IGP

Configuring a Master Tunnel

You need to configure the CBTS feature only on the tunnel headend. No CBTS configuration is required on the tailend or transit LSR.

Creating Multiple MPLS TE or DS-TE Tunnels from the Same Headend to the Same Tailend

Figure 1 shows an example of two tunnels, Tunnel 65 and Tunnel 66, transporting different classes of traffic between the same headend and the same tailend.

Figure 1 Tunnels Transporting Different Classes of Service Between the Same Headend and Tailend

SUMMARY STEPS

1. enable

2. configure terminal

3. interface tunnel number

4. ip unnumbered type number

5. tunnel destination {hostname | ip-address}

6. tunnel mode mpls traffic-eng

7. tunnel mpls traffic-eng bandwidth [sub-pool | global] bandwidth

8. exit

9. Repeat steps 3 through 8 on the same headend router to create additional tunnels from this headend to the same tailend.

10. end

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

interface tunnel number

Example:

Router(config)# interface tunnel 65

Configures an interface type and enters interface configuration mode.

Step 4 

ip unnumbered type number

Example:

Router(config-if)# ip unnumbered loopback 0

Enables IP processing on an interface without assigning an explicit IP address to the interface.

Step 5 

tunnel destination {hostname | ip-address}

Example:

Router(config-if)# tunnel destination 10.10.10.12

Specifies the destination of the tunnel for this path option.

Step 6 

tunnel mode mpls traffic-eng

Example:

Router(config-if)# tunnel mode mpls traffic-eng

Sets the mode of a tunnel to MPLS for TE.

Step 7 

tunnel mpls traffic-eng bandwidth [sub-pool | global] bandwidth

Example:

Router(config-if)# tunnel mpls traffic-eng bandwidth sub-pool 3000

Configures the bandwidth for the MPLS TE tunnel. If automatic bandwidth is configured for the tunnel, use the tunnel mpls traffic-eng bandwidth command to configure the initial tunnel bandwidth, which is adjusted by the autobandwidth mechanism.

Note You can configure any existing MPLS TE command on these TE or DS-TE tunnels.

Step 8 

exit

Example:

Router(config-if)# exit

Returns to global configuration mode.

Step 9 

Repeat steps 3 through 8 on the same headend router to create additional tunnels from this headend to the same tailend.

Step 10 

end

Example:

Router(config)# end

Returns to privileged EXEC mode.

Configuring EXP Values to Be Carried by Each MPLS TE or DS-TE Tunnel

For each tunnel that you create, you must indicate which EXP values the tunnel carries.

SUMMARY STEPS

1. enable

2. configure terminal

3. interface type number

4. tunnel mpls traffic-eng exp [list-of-exp-values] [default]

5. exit

6. Repeat steps 3 through 5 for all MPLS TE tunnels that you created in the "Creating Multiple MPLS TE or DS-TE Tunnels from the Same Headend to the Same Tailend" section.

7. end

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

interface type number

Example:

Router(config)# interface tunnel 65

Configures an interface type and enters interface configuration mode.

Step 4 

tunnel mpls traffic-eng exp [list-of-exp-values] [default]

Example:

Router(config-if)# tunnel mpls traffic-eng exp 5

Specifies the EXP bits that will be forwarded over a member tunnel that is part of the CBTS bundle.

Step 5 

exit

Example:

Router(config-if)# exit

Returns to global configuration mode.

Step 6 

Repeat steps 3 through 5 for all MPLS TE tunnels that you created in the "Creating Multiple MPLS TE or DS-TE Tunnels from the Same Headend to the Same Tailend" section.

Step 7 

end

Example:

Router(config-if)# end

Returns to privileged EXEC mode.

Making the MPLS TE or DS-TE Tunnels Visible for Routing


Note Alternatively, you can use static routing instead of autoroute to make the TE or DS-TE tunnels visible for routing.


SUMMARY STEPS

1. enable

2. configure terminal

3. interface type number

4. tunnel mpls traffic-eng autoroute announce

5. tunnel mpls traffic-eng autoroute metric {absolute | relative} value

6. end

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

interface type number

Example:

Router(config)# interface tunnel 65

Configures an interface type and enters interface configuration mode.

Step 4 

tunnel mpls traffic-eng autoroute announce

Example:

Router(config-if)# tunnel mpls traffic-eng autoroute announce

Specifies that the Interior Gateway Protocol (IGP) should use the tunnel (if the tunnel is up) in its enhanced SPF calculation.

Step 5 

tunnel mpls traffic-eng autoroute metric {absolute | relative} value

Example:

Router(config-if)# tunnel mpls traffic-eng autoroute metric relative 2

Specifies the MPLS TE tunnel metric that the IGP enhanced SPF calculation uses.

Note Even though the value for a relative metric can be from -10 to +10, configuring a tunnel metric with a negative value is considered a misconfiguration. If the metric to the tunnel tailend appears to be 4 from the routing table, then the cost to the tunnel tailend router is actually 3 because 1 is added to the cost for getting to the loopback address. In this instance, the lowest value that you can configure for the relative metric is -3.

Step 6 

end

Example:

Router(config-if)# end

Returns to privileged EXEC mode.

Verifying That the MPLS TE or DS-TE Tunnels Are Operating and Announced to the IGP

SUMMARY STEPS

1. show mpls traffic-eng topology {ip-address | igp-id {isis nsap-address | ospf ip-address} [brief]

2. show mpls traffic-eng tunnels number [brief] protect

3. show ip cef [vrf vrf-name] [unresolved [detail] | [detail | summary]]

4. show mpls forwarding-table [network {mask | length} | labels label [- label] | interface interface | next-hop address | lsp-tunnel [tunnel-id]] [vrf vrf-name] [detail]

5. show mpls traffic-eng autoroute


DETAILED STEPS


Step 1 show mpls traffic-eng topology {ip-address | igp-id {isis nsap-address | ospf ip-address} [brief]

Use this command to display the MPLS TE global topology currently known at this node:

Router# show mpls traffic-eng topology
 
   
My_System_id: 0000.0025.0003.00
 
IGP Id: 0000.0024.0004.00, MPLS TE Id:172.16.4.4 Router Node
      link[0 ]:Intf Address: 10.1.1.4
                  Nbr IGP Id: 0000.0024.0004.02, 
                admin_weight:10, affinity_bits:0x0
                max_link_bw:10000 max_link_reservable: 10000
	 	globalpool	subpool
               	total allocated	reservable 		reservable
               	--------------- 	---------- 	----------
	bw[0]: 	0 	1000	500
	bw[1]:	10 	990	490
	bw[2]: 	600 	390	390
	bw[3]: 	0 	390	390
	bw[4]: 	0 	390	390
	bw[5]: 	0 	390	390
 
   
 
   

Step 2 show mpls traffic-eng tunnels number [brief] [protection]

Use this command to display information for a specified tunneling interface:

Router# show mpls traffic-eng tunnels 500 brief protection 
 
   
Router#_t500
  LSP Head, Tunnel500, Admin: up, Oper: up
  Src 172.16.0.5, Dest 172.16.0.8, Instance 17
  Fast Reroute Protection: None
  Path Protection: 1 Common Link(s) , 1 Common Node(s)
    Primary lsp path:192.168.6.6 192.168.7.7
                     192.168.8.8 192.168.0.8
 
   
    Protect lsp path:172.16.7.7 192.168.8.8
                     10.0.0.8
    Path Protect Parameters:
      Bandwidth: 50       kbps (Global)  Priority: 7  7   Affinity: 0x0/0xFFFF
      Metric Type: TE (default)
    InLabel  :  -
    OutLabel : Serial5/3, 46
    RSVP Signalling Info:
         Src 172.16.0.5, Dst 172.16.0.8, Tun_Id 500, Tun_Instance 18
      RSVP Path Info:
        My Address: 172.16.0.5
        Explicit Route: 192.168.7.7 192.168.8.8
        Record   Route:   NONE
        Tspec: ave rate=50 kbits, burst=1000 bytes, peak rate=50 kbits
      RSVP Resv Info:
        Record   Route:   NONE
        Fspec: ave rate=50 kbits, burst=1000 bytes, peak rate=50 kbits
 
   

Step 3 show ip cef summary

Use this command to display a summary of the IP CEF table:

Router# show ip cef summary
 
   
IP Distributed CEF with switching (Table Version 25), flags=0x0
 21 routes, 0 reresolve, 0 unresolved (0 old, 0 new), peak 1
 21 leaves, 16 nodes, 19496 bytes, 36 inserts, 15 invalidations
 0 load sharing elements, 0 bytes, 0 references
 universal per-destination load sharing algorithm, id 5163EC15
 3(0) CEF resets, 0 revisions of existing leaves
 Resolution Timer: Exponential (currently 1s, peak 1s)
 0 in-place/0 aborted modifications
 refcounts:  4377 leaf, 4352 node
 
   
 Table epoch: 0 (21 entries at this epoch)
 
   
 Adjacency Table has 9 adjacencies
 
   

Step 4 show mpls forwarding-table [network {mask | length} | labels label [- label] | interface interface | next-hop address | lsp-tunnel [tunnel-id]] [vrf vrf-name] [detail]

Use this command to display the contents of the MPLS Label Forwarding Information Base (LFIB):

Router# show mpls forwarding-table
 
   
Local Outgoing      Prefix            Bytes tag Outgoing       Next Hop       
Label Label or VC   or Tunnel Id      switched  interface                     
26    No Label      10.253.0.0/16     0         Et4/0/0       10.27.32.4    
28    1/33          10.15.0.0/16      0         AT0/0.1       point2point    
29    Pop Label     10.91.0.0/16      0         Hs5/0         point2point    
      1/36          10.91.0.0/16      0         AT0/0.1       point2point    
30    32            10.250.0.97/32    0         Et4/0/2       10.92.0.7      
      32            10.250.0.97/32    0         Hs5/0         point2point    
34    26            10.77.0.0/24      0         Et4/0/2       10.92.0.7      
      26            10.77.0.0/24      0         Hs5/0         point2point    
35    No Label[T]   10.100.100.101/32 0         Tu301         point2point    
36    Pop Label     10.1.0.0/16      0         Hs5/0         point2point    
      1/37          10.1.0.0/16      0         AT0/0.1       point2point    
 
   
[T]     Forwarding through a TSP tunnel.
        View additional tagging info with the 'detail' option
 
   

Step 5 show mpls traffic-eng autoroute

Use this command to display tunnels that are announced to the IGP, including interface, destination, and bandwidth:

Router# show mpls traffic-eng autoroute
 
   
MPLS TE autorouting enabled
  destination 0002.0002.0002.00 has 2 tunnels
    Tunnel1021 (traffic share 10000, nexthop 10.2.2.2, absolute metric 11)
    Tunnel1022 (traffic share 3333, nexthop 10.2.2.2, relative metric -3)
  destination 0003.0003.0003.00 has 2 tunnels
    Tunnel1032 (traffic share 10000, nexthop 172.16.3.3)
    Tunnel1031 (traffic share 10000, nexthop 172.16.3.3, relative metric -1)
 
   

Configuring a Master Tunnel

SUMMARY STEPS

1. enable

2. configure terminal

3. interface tunnel number

4. ip unnumbered type number

5. tunnel destination {hostname | ip-address}

6. tunnel mode mpls traffic-eng

7. tunnel mpls traffic-eng exp-bundle master

8. tunnel mpls traffic-eng exp-bundle member tunnel-number

9. exit

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

interface tunnel number

Example:

Router(config)# interface tunnel 65

Configures an interface type and enters interface configuration mode.

Step 4 

ip unnumbered type number

Example:

Router(config-if)# ip unnumbered loopback 0

Enables IP processing on an interface without assigning an explicit IP address to the interface.

Step 5 

tunnel destination {hostname | ip-address}

Example:

Router(config-if)# tunnel destination 10.10.10.12

Specifies the destination of the tunnel for this path option.

Step 6 

tunnel mode mpls traffic-eng

Example:

Router(config-if)# tunnel mode mpls traffic-eng

Sets the mode of a tunnel to MPLS for TE.

Step 7 

tunnel mpls traffic-eng exp-bundle master

Example:

Router(config-if)# tunnel mpls traffic-eng exp-bundle master

Configures a master tunnel.

Step 8 

tunnel mpls traffic-eng exp-bundle member tunnel-number

Example:

Router(config-if)# tunnel mpls traffic-eng exp-bundle member tunnel1

Identifies which tunnel is a member of a master tunnel.

Step 9 

exit

Example:

Router(config-if)# exit

Exits to global configuration mode.

Configuration Examples for MPLS Traffic Engineering : Class-based Tunnel Selection

Creating Multiple MPLS TE or DS-TE Tunnels from the Same Headend to the Same Tailend: Example

Configuring EXP Values to Be Carried by Each MPLS TE or DS-TE Tunnel: Example

Making the MPLS TE or DS-TE Tunnels Visible for Routing: Example

Verifying That the MPLS TE or DS-TE Tunnels Are Operating and Announced to the IGP: Example

Configuring a Master Tunnel: Example

Creating Multiple MPLS TE or DS-TE Tunnels from the Same Headend to the Same Tailend: Example

The following example shows how to create multiple MPLS TE or DS-TE tunnels from the same headend to the same tailend:

Router(config)# interface Tunnel 65 
Router(config-if)# ip numbered loopback 0
Router(config-if)# tunnel destination 10.1.1.1 
Router(config-if)# tunnel mode mpls traffic-eng
Router(config-if)# tunnel mpls traffic-eng bandwidth sub-pool 30000 
Router(config-if)# ^Z
Router(config)# interface Tunnel 66 
Router(config-if)# ip numbered loopback 0
Router(config-if)# tunnel destination 10.1.1.1 
Router(config-if)# tunnel mode mpls traffic-eng
Router(config-if)# tunnel mpls traffic-eng bandwidth 50000
Router(config-if)# end
Router# 

Configuring EXP Values to Be Carried by Each MPLS TE or DS-TE Tunnel: Example

The following example shows how to configure EXP values to be carried by each MPLS TE or DS-TE tunnel that you created:

Router(config)# interface Tunnel 65 
Router(config-if)# tunnel mpls traffic-eng exp 5
Router(config-if)# ^Z
Router(config)# 
Router(config)# interface Tunnel 66 
Router(config-if)# tunnel mpls traffic-eng exp 0 1 2 3 4 6 7
Router(config-if)# end
Router#

Making the MPLS TE or DS-TE Tunnels Visible for Routing: Example

The following example shows how to make the MPLS TE or DS-TE tunnels visible for routing:

Router(config)# interface Tunnel 65 
Router(config-if)# tunnel mpls traffic-eng autoroute announce
Router(config-if)# tunnel mpls traffic-eng autoroute metric relative -2
Router(config-if)# ^Z
Router(config)# 
Router(config)# interface Tunnel 66 
Router(config-if)# tunnel mpls traffic-eng autoroute announce
Router(config-if)# tunnel mpls traffic-eng autoroute metric relative -2
Router(config-if)# end
Router#
 
   

Packets destined beyond 10.1.1.1 are sent on:

Tunnel 65 if their EXP value after input MQC is 5.

Tunnel 66 if their EXP value after input MQC is 0, 1, 2, 3, 4, 6, or 7.

Verifying That the MPLS TE or DS-TE Tunnels Are Operating and Announced to the IGP: Example

The output for each of the following examples helps verify that the MPLS TE or DS-TE tunnels are operating and visible.

The show mpls traffic-eng topology command output displays the MPLS TE global topology:

Router# show mpls traffic-eng topology 10.0.0.1
 
   
IGP Id: 10.0.0.1, MPLS TE Id:10.0.0.1 Router Node  (ospf 10  area 0) id 1
      link[0]: Broadcast, DR: 10.0.1.2, nbr_node_id:6, gen:18
	  frag_id 0, Intf Address:10.1.1.1
	  TE metric:1, IGP metric:1, attribute_flags:0x0
	  SRLGs: None 
	  physical_bw: 100000 (kbps), max_reservable_bw_global: 1000 (kbps)
	  max_reservable_bw_sub: 0 (kbps)
 
   
	                         Global Pool       Sub Pool
	       Total Allocated   Reservable        Reservable
	       BW (kbps)         BW (kbps)         BW (kbps)
	       ---------------   -----------       ----------
	bw[0]:            0             1000                0
	bw[1]:            0             1000                0
	bw[2]:            0             1000                0
	bw[3]:            0             1000                0
	bw[4]:            0             1000                0
	bw[5]:            0             1000                0
	bw[6]:            0             1000                0
	bw[7]:          100              900                0
 
   
      link[1]: Broadcast, DR: 10.0.2.2, nbr_node_id:7, gen:19
	  frag_id 1, Intf Address:10.0.2.1
	  TE metric:1, IGP metric:1, attribute_flags:0x0
	  SRLGs: None 
	  physical_bw: 100000 (kbps), max_reservable_bw_global: 1000 (kbps)
	  max_reservable_bw_sub: 0 (kbps)
 
   
	                         Global Pool       Sub Pool
	       Total Allocated   Reservable        Reservable
	       BW (kbps)         BW (kbps)         BW (kbps)
	       ---------------   -----------       ----------
	bw[0]:            0             1000                0
	bw[1]:            0             1000                0
	bw[2]:            0             1000                0
	bw[3]:            0             1000                0
	bw[4]:            0             1000                0
	bw[5]:            0             1000                0
	bw[6]:            0             1000                0
	bw[7]:          300              700                0
Router#
 
   
Router# show mpls traffic-eng topology 10.0.0.9
 
   
IGP Id: 10.0.0.9, MPLS TE Id:10.0.0.9 Router Node  (ospf 10  area 0) id 3
      link[0]: Point-to-Point, Nbr IGP Id: 10.0.0.5, nbr_node_id:5, gen:9
	  frag_id 1, Intf Address:10.0.5.2, Nbr Intf Address:10.0.5.1
	  TE metric:1, IGP metric:1, attribute_flags:0x0
	  SRLGs: None 
	  physical_bw: 155000 (kbps), max_reservable_bw_global: 1000 (kbps)
	  max_reservable_bw_sub: 0 (kbps)
 
   
	                         Global Pool       Sub Pool
	       Total Allocated   Reservable        Reservable
	       BW (kbps)         BW (kbps)         BW (kbps)
	       ---------------   -----------       ----------
	bw[0]:            0             1000                0
	bw[1]:            0             1000                0
	bw[2]:            0             1000                0
	bw[3]:            0             1000                0
	bw[4]:            0             1000                0
	bw[5]:            0             1000                0
	bw[6]:            0             1000                0
	bw[7]:            0             1000                0
 
   
      link[1]: Point-to-Point, Nbr IGP Id: 10.0.0.7, nbr_node_id:4, gen:9
	  frag_id 0, Intf Address:10.0.6.2, Nbr Intf Address:10.0.6.1
	  TE metric:1, IGP metric:1, attribute_flags:0x0
	  SRLGs: None 
	  physical_bw: 155000 (kbps), max_reservable_bw_global: 1000 (kbps)
	  max_reservable_bw_sub: 0 (kbps)
 
   
	                         Global Pool       Sub Pool
	       Total Allocated   Reservable        Reservable
	       BW (kbps)         BW (kbps)         BW (kbps)
	       ---------------   -----------       ----------
	bw[0]:            0             1000                0
	bw[1]:            0             1000                0
	bw[2]:            0             1000                0
	bw[3]:            0             1000                0
	bw[4]:            0             1000                0
	bw[5]:            0             1000                0
	bw[6]:            0             1000                0
	bw[7]:            0             1000                0
Router#
 
   

The show mpls traffic-eng tunnels command output displays information about a tunnel:

Router# show mpls traffic-eng tunnels tunnel1
 
   
Name: Router_t1                            (Tunnel1) Destination: 10.0.0.9
  Status:
    Admin: up         Oper: up     Path: valid       Signalling: connected
    path option 1, type explicit path1 (Basis for Setup, path weight 3)
 
   
  Config Parameters:
    Bandwidth: 100      kbps (Global)  Priority: 7  7   Affinity: 0x0/0xFFFF
    Metric Type: TE (default)
    AutoRoute:  enabled   LockDown: disabled  Loadshare: 100      bw-based
    auto-bw: disabled
  Active Path Option Parameters:
    State: explicit path option 1 is active
    BandwidthOverride: disabled  LockDown: disabled  Verbatim: disabled
 
   
 
   
  InLabel  :  - 
  OutLabel : FastEthernet6/0, 12304
  RSVP Signalling Info:
       Src 10.0.0.1, Dst 10.0.0.9, Tun_Id 1, Tun_Instance 10
    RSVP Path Info:
      My Address: 10.0.1.1   
      Explicit Route: 10.0.1.2 10.0.3.2 10.0.5.2 10.0.0.9 
      Record   Route:   NONE
      Tspec: ave rate=100 kbits, burst=1000 bytes, peak rate=100 kbits
    RSVP Resv Info:
      Record   Route:   NONE
      Fspec: ave rate=100 kbits, burst=1000 bytes, peak rate=17179869 kbits
  Shortest Unconstrained Path Info:
    Path Weight: 3 (TE)
    Explicit Route: 10.0.2.1 180.0.2.2 10.0.3.2 180.0.5.2 
                    10.0.0.9 
  History:
    Tunnel:
      Time since created: 15 minutes, 18 seconds
      Time since path change: 15 minutes, 5 seconds
    Current LSP:
      Uptime: 15 minutes, 5 seconds
 
   
Router# show mpls traffic-eng tunnel tunnel2
 
   
Name: Router_t2                            (Tunnel2) Destination: 10.0.0.9
  Status:
    Admin: up         Oper: up     Path: valid       Signalling: connected
    path option 1, type explicit path2 (Basis for Setup, path weight 3)
 
   
  Config Parameters:
    Bandwidth: 100      kbps (Global)  Priority: 7  7   Affinity: 0x0/0xFFFF
    Metric Type: TE (default)
    AutoRoute:  enabled   LockDown: disabled  Loadshare: 100      bw-based
    auto-bw: disabled
  Active Path Option Parameters:
    State: explicit path option 1 is active
    BandwidthOverride: disabled  LockDown: disabled  Verbatim: disabled
 
   
 
   
  InLabel  :  - 
  OutLabel : FastEthernet6/1, 12305
  RSVP Signalling Info:
       Src 10.0.0.1, Dst 10.0.0.9, Tun_Id 2, Tun_Instance 10
    RSVP Path Info:
      My Address: 10.0.2.1   
      Explicit Route: 10.0.2.2  10.0.4.2  10.0.6.2 10.0.0.9 
      Record   Route:   NONE
      Tspec: ave rate=100 kbits, burst=1000 bytes, peak rate=100 kbits
    RSVP Resv Info:
      Record   Route:   NONE
      Fspec: ave rate=100 kbits, burst=1000 bytes, peak rate=17179869 kbits
  Shortest Unconstrained Path Info:
    Path Weight: 3 (TE)
    Explicit Route: 10.0.2.1 10.0.2.2 10.0.3.2 10.0.5.2 
                    10.0.0.9 
  History:
    Tunnel:
      Time since created: 15 minutes, 19 seconds
      Time since path change: 15 minutes, 6 seconds
    Current LSP:
      Uptime: 15 minutes, 6 seconds
 
   
 
   
Router# show mpls traffic-eng tunnels tunnel3
 
   
Name: Router_t3                            (Tunnel3) Destination: 10.0.0.9
  Status:
    Admin: up         Oper: up     Path: valid       Signalling: connected
    path option 1, type explicit path2 (Basis for Setup, path weight 3)
 
   
  Config Parameters:
    Bandwidth: 100      kbps (Global)  Priority: 7  7   Affinity: 0x0/0xFFFF
    Metric Type: TE (default)
    AutoRoute:  enabled   LockDown: disabled  Loadshare: 100      bw-based
    auto-bw: disabled
  Active Path Option Parameters:
    State: explicit path option 1 is active
    BandwidthOverride: disabled  LockDown: disabled  Verbatim: disabled
 
   
  InLabel  :  - 
  OutLabel : FastEthernet6/1, 12306
  RSVP Signalling Info:
       Src 10.0.0.1, Dst 10.0.0.9, Tun_Id 3, Tun_Instance 8
    RSVP Path Info:
      My Address: 10.0.2.1   
'     Explicit Route: 10.0.2.2 10.0.4.2 10.0.6.2 10.0.0.9 
      Record   Route:   NONE
      Tspec: ave rate=100 kbits, burst=1000 bytes, peak rate=100 kbits
    RSVP Resv Info:
      Record   Route:   NONE
      Fspec: ave rate=100 kbits, burst=1000 bytes, peak rate=17179869 kbits
  Shortest Unconstrained Path Info:
    Path Weight: 3 (TE)
    Explicit Route: 10.0.2.1 10.0.2.2 10.0.3.2 10.0.5.2 
                    10.0.0.9 
  History:
    Tunnel:
      Time since created: 15 minutes, 19 seconds
      Time since path change: 15 minutes, 7 seconds
    Current LSP:
      Uptime: 15 minutes, 7 seconds
 
   
 
   
Router# show mpls traffic-eng tunnels tunnel4
 
   
Name: Router_t4                            (Tunnel4) Destination: 10.0.0.9
  Status:
    Admin: up         Oper: up     Path: valid       Signalling: connected
    path option 1, type explicit path2 (Basis for Setup, path weight 3)
 
   
  Config Parameters:
    Bandwidth: 100      kbps (Global)  Priority: 7  7   Affinity: 0x0/0xFFFF
    Metric Type: TE (default)
    AutoRoute:  enabled   LockDown: disabled  Loadshare: 100      bw-based
    auto-bw: disabled
  Active Path Option Parameters:
    State: explicit path option 1 is active
    BandwidthOverride: disabled  LockDown: disabled  Verbatim: disabled
 
   
  InLabel  :  - 
  OutLabel : FastEthernet6/1, 12307
  RSVP Signalling Info:
       Src 10.0.0.1, Dst 10.0.0.9, Tun_Id 4, Tun_Instance 6
    RSVP Path Info:
      My Address: 10.0.2.1   
      Explicit Route: 10.0.2.2 10.0.4.2 10.0.6.2 10.0.0.9 
      Record   Route:   NONE
      Tspec: ave rate=100 kbits, burst=1000 bytes, peak rate=100 kbits
    RSVP Resv Info:
      Record   Route:   NONE
      Fspec: ave rate=100 kbits, burst=1000 bytes, peak rate=17179869 kbits
  Shortest Unconstrained Path Info:
    Path Weight: 3 (TE)
    Explicit Route: 10.0.2.1 10.0.2.2 10.0.3.2 10.0.5.2 
                    10.0.0.9 
  History:
    Tunnel:
      Time since created: 15 minutes, 20 seconds
      Time since path change: 15 minutes, 8 seconds
    Current LSP:
      Uptime: 15 minutes, 8 seconds
 
   
 
   

The show ip cef detail command output displays detailed FIB entry information for a tunnel:

Router# show ip cef tunnel1 detail
 
   
IP CEF with switching (Table Version 46), flags=0x0
  31 routes, 0 reresolve, 0 unresolved (0 old, 0 new), peak 2
  2 instant recursive resolutions, 0 used background process
  8 load sharing elements, 8 references
  6 in-place/0 aborted modifications
  34696 bytes allocated to the FIB table data structures
  universal per-destination load sharing algorithm, id 9EDD49E1
  1(0) CEF resets
  Resolution Timer: Exponential (currently 1s, peak 1s)
  Tree summary:
   8-8-8-8 stride pattern
   short mask protection disabled
   31 leaves, 23 nodes using 26428 bytes
 
   
  Table epoch: 0 (31 entries at this epoch)
 
   
Adjacency Table has 13 adjacencies
10.0.0.9/32, version 45, epoch 0, per-destination sharing
0 packets, 0 bytes
  tag information set, all rewrites inherited
    local tag: tunnel head
  via 0.0.0.0, Tunnel1, 0 dependencies
    traffic share 1
    next hop 0.0.0.0, Tunnel1
    valid adjacency
    tag rewrite with Tu1, point2point, tags imposed {12304}
  0 packets, 0 bytes switched through the prefix
  tmstats: external 0 packets, 0 bytes
           internal 0 packets, 0 bytes
 
   
 
   
Router# show ip cef tunnel2 detail
 
   
IP CEF with switching (Table Version 46), flags=0x0
  31 routes, 0 reresolve, 0 unresolved (0 old, 0 new), peak 2
  2 instant recursive resolutions, 0 used background process
  8 load sharing elements, 8 references
  6 in-place/0 aborted modifications
  34696 bytes allocated to the FIB table data structures
  universal per-destination load sharing algorithm, id 9EDD49E1
  1(0) CEF resets
  Resolution Timer: Exponential (currently 1s, peak 1s)
  Tree summary:
   8-8-8-8 stride pattern
   short mask protection disabled
   31 leaves, 23 nodes using 26428 bytes
 
   
  Table epoch: 0 (31 entries at this epoch)
 
   
Adjacency Table has 13 adjacencies
10.0.0.9/32, version 45, epoch 0, per-destination sharing
0 packets, 0 bytes
  tag information set, all rewrites inherited
    local tag: tunnel head
  via 0.0.0.0, Tunnel2, 0 dependencies
    traffic share 1
    next hop 0.0.0.0, Tunnel2
    valid adjacency
    tag rewrite with Tu2, point2point, tags imposed {12305}
  0 packets, 0 bytes switched through the prefix
  tmstats: external 0 packets, 0 bytes
           internal 0 packets, 0 bytes
 
   
 
   
Router# show ip cef tunnel3 detail
 
   
IP CEF with switching (Table Version 46), flags=0x0
  31 routes, 0 reresolve, 0 unresolved (0 old, 0 new), peak 2
  2 instant recursive resolutions, 0 used background process
  8 load sharing elements, 8 references
  6 in-place/0 aborted modifications
  34696 bytes allocated to the FIB table data structures
  universal per-destination load sharing algorithm, id 9EDD49E1
  1(0) CEF resets
  Resolution Timer: Exponential (currently 1s, peak 1s)
  Tree summary:
   8-8-8-8 stride pattern
   short mask protection disabled
   31 leaves, 23 nodes using 26428 bytes
 
   
  Table epoch: 0 (31 entries at this epoch)
 
   
Adjacency Table has 13 adjacencies
10.0.0.9/32, version 45, epoch 0, per-destination sharing
0 packets, 0 bytes
  tag information set, all rewrites inherited
    local tag: tunnel head
  via 0.0.0.0, Tunnel3, 0 dependencies
    traffic share 1
    next hop 0.0.0.0, Tunnel3
    valid adjacency
    tag rewrite with Tu3, point2point, tags imposed {12306}
  0 packets, 0 bytes switched through the prefix
  tmstats: external 0 packets, 0 bytes
           internal 0 packets, 0 bytes
 
   
 
   
Router# show ip cef tunnel4 detail
 
   
IP CEF with switching (Table Version 46), flags=0x0
  31 routes, 0 reresolve, 0 unresolved (0 old, 0 new), peak 2
  2 instant recursive resolutions, 0 used background process
  8 load sharing elements, 8 references
  6 in-place/0 aborted modifications
  34696 bytes allocated to the FIB table data structures
  universal per-destination load sharing algorithm, id 9EDD49E1
  1(0) CEF resets
  Resolution Timer: Exponential (currently 1s, peak 1s)
  Tree summary:
   8-8-8-8 stride pattern
   short mask protection disabled
   31 leaves, 23 nodes using 26428 bytes
 
   
  Table epoch: 0 (31 entries at this epoch)
 
   
Adjacency Table has 13 adjacencies
10.0.0.9/32, version 45, epoch 0, per-destination sharing
0 packets, 0 bytes
  tag information set, all rewrites inherited
    local tag: tunnel head
  via 0.0.0.0, Tunnel4, 0 dependencies
    traffic share 1
    next hop 0.0.0.0, Tunnel4
    valid adjacency
    tag rewrite with Tu4, point2point, tags imposed {12307}
  0 packets, 0 bytes switched through the prefix
  tmstats: external 0 packets, 0 bytes
           internal 0 packets, 0 bytes
 
   
 
   

The show mpls forwarding-table detail command output displays detailed information from the MPLS LFIB:

Router# show mpls forwarding-table detail
 
   
Local  Outgoing    Prefix            Bytes tag  Outgoing   Next Hop    
tag    tag or VC   or Tunnel Id      switched   interface              
Router#
 
   
Router# show mpls forwarding-table 10.0.0.9 detail
 
   
Local  Outgoing    Prefix            Bytes tag  Outgoing   Next Hop    
tag    tag or VC   or Tunnel Id      switched   interface              
Tun hd Untagged    10.0.0.9/32       0          Tu1        point2point  
	MAC/Encaps=14/18, MRU=1500, Tag Stack{12304}, via Fa6/0
	00027D884000000ED70178A88847 03010000
	No output feature configured
        Per-exp selection: 1  
       Untagged    10.0.0.9/32       0          Tu2        point2point  
	MAC/Encaps=14/18, MRU=1500, Tag Stack{12305}, via Fa6/1
	00027D884001000ED70178A98847 03011000
	No output feature configured
        Per-exp selection: 2  3  
       Untagged    10.0.0.9/32       0          Tu3        point2point  
	MAC/Encaps=14/18, MRU=1500, Tag Stack{12306}, via Fa6/1
	00027D884001000ED70178A98847 03012000
	No output feature configured
        Per-exp selection: 4  5  
       Untagged    10.0.0.9/32       0          Tu4        point2point  
	MAC/Encaps=14/18, MRU=1500, Tag Stack{12307}, via Fa6/1
	00027D884001000ED70178A98847 03013000
	No output feature configured
        Per-exp selection: 0  6  7  
Router#
 
   
 
   

The show mpls traffic-eng autoroute command output displays tunnels that are announced to the IGP:

Router# show mpls traffic-eng autoroute 
 
   
MPLS TE autorouting enabled
  destination 10.0.0.9, area ospf 10  area 0, has 4 tunnels
    Tunnel1     (load balancing metric 20000000, nexthop 10.0.0.9)
                (flags: Announce)
    Tunnel2     (load balancing metric 20000000, nexthop 10.0.0.9)
                (flags: Announce)
    Tunnel3     (load balancing metric 20000000, nexthop 10.0.0.9)
                (flags: Announce)
    Tunnel4     (load balancing metric 20000000, nexthop 10.0.0.9)
                (flags: Announce)
Router#
 
   

Configuring a Master Tunnel: Example

The following example specifies that there is a master tunnel that includes tunnels Tunnel20000 through Tunnel20005:

interface Tunnel 200
 ip unnumbered Loopback 0
 tunnel destination 10.10.10.10
 tunnel mode mpls traffic-eng
 tunnel mpls traffic-eng exp-bundle master
 tunnel mpls traffic-eng exp-bundle member Tunnel20000
 tunnel mpls traffic-eng exp-bundle member Tunnel20001
 tunnel mpls traffic-eng exp-bundle member Tunnel20002
 tunnel mpls traffic-eng exp-bundle member Tunnel20003
 tunnel mpls traffic-eng exp-bundle member Tunnel20004
 tunnel mpls traffic-eng exp-bundle member Tunnel20005

Additional References

Related Documents

Related Topic
Document Title

MPLS traffic engineering commands

Cisco IOS Multiprotocol Label Switching Command Reference


Standards

Standard
Title

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


MIBs

MIB
MIBs Link

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

To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

http://www.cisco.com/go/mibs


RFCs

RFC
Title

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


Technical Assistance

Description
Link

The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.

To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.

Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

http://www.cisco.com/techsupport


Feature Information for MPLS Traffic Engineering : Class-based Tunnel Selection

Table 1 lists the release history for this feature.

Not all commands may be available in your Cisco IOS software release. For release information about a specific command, see the command reference documentation.

Cisco IOS software images are specific to a Cisco IOS software release, a feature set, and a platform. Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at the login dialog box and follow the instructions that appear.


Note Table 1 lists only the Cisco IOS software release that introduced support for a given feature in a given Cisco IOS software release train. Unless noted otherwise, subsequent releases of that Cisco IOS software release train also support that feature.


Table 1 Feature Information for MPLS Traffic Engineering : Class-based Tunnel Selection

Feature Name
Releases
Feature Configuration Information

MPLS Traffic Engineering : Class-based Tunnel Selection

12.0(29)S
12.2(33)SRA
12.2(32)SY
12.2(33)SXH
12.4(20)T

The MPLS Traffic Engineering (TE): Class-based Tunnel Selection feature enables you to dynamically route and forward traffic with different class of service (CoS) values onto different TE tunnels between the same tunnel headend and the same tailend. The TE tunnels can be regular TE or DiffServ-aware TE (DS-TE) tunnels.

In 12.0(29)S, this feature was introduced.

In 12.2(33)SRA, this feature was integrated and the following commands were added:

tunnel mpls traffic-eng exp-bundle master

tunnel mpls traffic-eng exp-bundle member

12.0(32)SY, support for this feature was added on the Cisco 12000 family of routers.

In 12.2(33)SXH, this feature was integrated.

In 12.4(20)T, this feature was integrated.


Glossary

BGP—Border Gateway Protocol. Interdomain routing protocol that replaces External Gateway Protocol (EGP). BGP exchanges reachability information with other BGP systems. It is defined by RFC 116.3

bundled tunnels—Members of a master tunnel. You define the EXP bits that will be forwarded over each bundled tunnel.

Cisco Express Forwarding—An advanced Layer 3 IP switching technology. Cisco Express Forwarding optimizes network performance and scalability for networks with large and dynamic traffic patterns, such as the Internet and networks characterized by intensive web-based applications or interactive sessions.

CoS—class of service. An indication of how an upper-layer protocol requires a lower-layer protocol to treat its messages. In Systems Network Architecture (SNA) subarea routing, CoS definitions are used by subarea nodes to determine the optimal route for establishing a given session. A CoS definition comprises a virtual route number and a transmission priority field. Also called type of service (ToS).

DS-TE—DiffServ-aware traffic engineering. The configuring of two bandwidth pools on each link, a global pool and a subpool. Multiprotocol Label Switching (MPLS) traffic engineering tunnels using the subpool bandwidth can be configured with quality of service (QoS) mechanisms to deliver guaranteed bandwidth services end-to-end across the network. Simultaneously, tunnels using the global pool can convey DiffServ traffic.

EXP—experimental field or bits. A 3-bit field in the Multiprotocol Label Switching (MPLS) header widely known as the EXP field or EXP bits because, according to RFC 3032, that field is reserved for experimental use. However, the most common use of those bits is for quality of service (QoS) purposes.

headend—The upstream, transmitting end of a tunnel. This is the first router in the label switched path (LSP).

LSP—label switched path. A sequence of hops (R0...Rn) in which a packet travels from R0 to Rn through label switching mechanisms. A label switched path can be chosen dynamically, based on normal routing mechanisms, or through configuration.

master tunnel—A set of tunnels that have the same destination.

MPLS traffic engineering—Multiprotocol Label Switching traffic engineering. A constraint-based routing algorithm for routing label switched path (LSP) tunnels.

MQC—modular quality of service (QoS) command-line interface (CLI). A CLI structure that allows users to create traffic polices and attach those polices to interfaces.

PBR—policy-based routing. A routing scheme in which packets are forwarded to specific interfaces based on user-configured policies. A policy might specify, for example, that traffic sent from a particular network should be forwarded out one interface, and all other traffic should be forwarded out another interface.

tailend—The downstream, receiving end of a tunnel. The router that terminates the traffic engineering label switched path (LSP).

TE—traffic engineering. The techniques and processes used to cause routed traffic to travel through the network on a path other than the one that would have been chosen if standard routing methods had been used.

ToS—type of service. See CoS.

tunnel—A secure communication path between two peers, such as two routers. A traffic engineering tunnel is a label-switched tunnel that is used for traffic engineering. Such a tunnel is set up through means other than normal Layer 3 routing; it is used to direct traffic over a path different from the one that Layer 3 routing could cause the tunnel to take.