- Read Me First
- MPLS Traffic Engineering and Enhancements
- MPLS Traffic Engineering Configurable Path Calculation Metric for Tunnels
- MPLS Traffic Engineering--Scalability Enhancements
- MPLS Traffic Engineering--LSP Attributes
- MPLS Traffic Engineering AutoTunnel Mesh Groups
- MPLS Traffic Engineering Verbatim Path Support
- MPLS Traffic Engineering--RSVP Hello State Timer
- MPLS Traffic Engineering Forwarding Adjacency
- MPLS Traffic Engineering Class-based Tunnel Selection
- MPLS Traffic Engineering Interarea Tunnels
- MPLS Traffic Engineering Static IPv6 Routes over MPLS TE IPv4 Tunnels
- MPLS Traffic Engineering Automatic Bandwidth Adjustment for TE Tunnels
- MPLS Traffic Engineering – Bundled Interface Support
- RSVP Refresh Reduction and Reliable Messaging
- Finding Feature Information
- Prerequisites for MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels
- Restrictions for MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels
- Information About MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels
- How to Configure MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels
- Configuring a Platform to Support Traffic Engineering Tunnels
- Configuring IS-IS for MPLS Traffic Engineering
- Configuring Traffic Engineering Link Metrics
- Configuring an MPLS Traffic Engineering Tunnel
- Configuring the Metric Type for Tunnel Path Calculation
- Verifying the Tunnel Path Metric Configuration
- Configuration Examples for Configuring a Path Calculation Metric for Tunnels
- Additional References
- Feature Information for MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels
MPLS Traffic Engineering Configurable Path Calculation Metric for Tunnels
The MPLS Traffic Engineering--Configurable Path Calculation Metric for Tunnels feature enables the user to control the metric used in path calculation for traffic engineering (TE) tunnels on a per-tunnel basis. Certain tunnels are used to carry voice traffic, which requires low delay, and other tunnels are used to carry data. A TE link metric can be used to represent link delay and configure tunnels that carry voice traffic for path calculation and configure tunnels that carry data to use the Interior Gateway Protocol (IGP) metric for path calculation.
- Finding Feature Information
- Prerequisites for MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels
- Restrictions for MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels
- Information About MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels
- How to Configure MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels
- Configuration Examples for Configuring a Path Calculation Metric for Tunnels
- Additional References
- Feature Information for MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Prerequisites for MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels
Before you configure tunnel path calculation metrics, your network must support the following Cisco IOS XE features:
Restrictions for MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels
-
Unless explicitly configured, the TE link metric for a given link is the IGP link metric. When the TE link metric is used to represent a link property that is different from cost/distance, you must configure every network link that can be used for TE tunnels with a TE link metric that represents that property by using the mpls traffic-eng administrative-weight command. Failure to do so might cause tunnels to use unexpected paths.
-
MPLS traffic engineering supports only a single IGP process/instance. Multiple IGP processes/instances are not supported and MPLS traffic engineering should not be configured in more than one IGP process/instance.
Information About MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels
Overview
When MPLS TE is configured in a network, the IGP floods two metrics for every link: the normal IGP (OSPF or IS-IS) link metric and a TE link metric. The IGP uses the IGP link metric in the normal way to compute routes for destination networks.
You can specify that the path calculation for a given tunnel be based on either of the following:
IGP link metrics.
TE link metrics, which you can configure so that they represent the needs of a particular application. For example, the TE link metrics can be configured to represent link transmission delay.
Benefits
When TE tunnels are used to carry two types of traffic, the Configurable Path Calculation Metric for Tunnels feature allows you to tailor tunnel path selection to the requirements of each type of traffic.
For example, suppose certain tunnels are to carry voice traffic (which requires low delay) and other tunnels are to carry data. In this situation, you can use the TE link metric to represent link delay and do the following:
Configure tunnels that carry voice to use the TE link metric set to represent link delay for path calculation.
Configure tunnels that carry data to use the IGP metric for path calculation.
How to Configure MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels
- Configuring a Platform to Support Traffic Engineering Tunnels
- Configuring IS-IS for MPLS Traffic Engineering
- Configuring Traffic Engineering Link Metrics
- Configuring an MPLS Traffic Engineering Tunnel
- Configuring the Metric Type for Tunnel Path Calculation
- Verifying the Tunnel Path Metric Configuration
Configuring a Platform to Support Traffic Engineering Tunnels
1.
enable
2.
configure
terminal
3.
ip
cef
distributed
4.
mpls
traffic-eng
tunnels
5.
exit
DETAILED STEPS
Configuring IS-IS for MPLS Traffic Engineering
To configure IS-IS for MPLS traffic engineering, perform the following steps.
Note | MPLS traffic engineering supports only a single IGP process/instance. Multiple IGP processes/instances are not supported and MPLS traffic engineering should not be configured in more than one IGP process/instance. |
1. Router(config)# router isis
2. Router(config-router)# mpls traffic-eng level-1
3. Router(config-router)# mpls traffic-eng level-2
4. Router(config-router)# mpls traffic-eng router-id loopback 0
5. Router(config-router)# metric-style wide
DETAILED STEPS
Command or Action | Purpose | |
---|---|---|
Step 1 | Router(config)# router isis |
Enables IS-IS routing and specifies an IS-IS process for IP. The router is placed in configuration mode. |
Step 2 | Router(config-router)# mpls traffic-eng level-1 |
Turns on MPLS traffic engineering for IS-IS level 1. |
Step 3 | Router(config-router)# mpls traffic-eng level-2 |
Turns on MPLS traffic engineering for IS-IS level 2. |
Step 4 | Router(config-router)# mpls traffic-eng router-id loopback 0 |
Specifies that the traffic engineering router identifier for the node is the IP address associated with interface loopback0. |
Step 5 | Router(config-router)# metric-style wide |
Configures a router to generate and accept only new-style type, length, value objects (TLVs). |
Configuring OSPF for MPLS Traffic Engineering
Note | MPLS traffic engineering supports only a single IGP process/instance. Multiple IGP processes/instances are not supported and MPLS traffic engineering should not be configured in more than one IGP process/instance. |
1.
enable
2.
configure
terminal
3.
router
ospf
process-id
4.
mpls
traffic-eng
area
number
5.
mpls
traffic-eng
router-id
loopback0
6.
exit
7.
exit
DETAILED STEPS
Configuring Traffic Engineering Link Metrics
Unless explicitly configured, the TE link metric is the IGP link metric.
1.
enable
2.
configure
terminal
3.
interface
type
slot
/
subslot
/
port
[. subinterface-number]
4.
mpls
traffic-eng
administrative-weight
weight
5.
exit
6.
exit
DETAILED STEPS
Configuring an MPLS Traffic Engineering Tunnel
This tunnel has two path setup options: a preferred explicit path and a backup dynamic path.
1.
enable
2.
configure
terminal
3.
interface
tunnel
number
4.
ip
unnumbered
type
number
5.
tunnel
destination
ip-address
6.
tunnel
mode
mpls
traffic-eng
7.
tunnel
mpls
traffic-eng
bandwidth
bandwidth
8.
tunnel
mpls
traffic-eng
path-option
number
{dynamic | explicit {name path-name | identifier path-number}} [lockdown]
9.
exit
10.
exit
DETAILED STEPS
Configuring the Metric Type for Tunnel Path Calculation
Unless explicitly configured, the TE link metric type is used for tunnel path calculation. Two commands are provided for controlling the metric type to be used: an interface configuration command that specifies the metric type to be used for a particular TE tunnel and a global configuration command that specifies the metric type to be used for TE tunnels for which a metric type has not been specified by the interface configuration command.
Note | If you do not enter either of the path selection metrics commands, the traffic engineering (TE) metric is used. |
1.
enable
2.
configure
terminal
3.
interface
tunnel
number
4.
tunnel
mpls
traffic-eng
path-selection
metric
{igp | te}
5.
exit
6.
mpls
traffic-eng
path-selection
metric
{igp | te}
7.
exit
DETAILED STEPS
Command or Action | Purpose | |
---|---|---|
Step 1 |
enable
Example: Router> enable |
Enables privileged EXEC mode.
|
Step 2 |
configure
terminal
Example: Router# configure terminal |
Enters global configuration mode. |
Step 3 |
interface
tunnel
number
Example: Router(config)# interface Tunnel0 |
Configures an interface type and enters interface configuration mode.
|
Step 4 |
tunnel
mpls
traffic-eng
path-selection
metric
{igp | te} Example: Router(config-if)# tunnel mpls traffic-eng path-selection metric igp |
Specifies the metric type to use for path calculation for a tunnel.
|
Step 5 |
exit
Example: Router(config-if)# exit |
Exits interface configuration mode and returns to global configuration mode. |
Step 6 |
mpls
traffic-eng
path-selection
metric
{igp | te} Example: Router(config)# mpls traffic-eng path-selection metric igp |
Specifies the metric type to use if a metric type was not explicitly configured for a given tunnel.
|
Step 7 |
exit
Example: Router(config)# exit |
Exits global configuration mode and returns to privileged EXEC mode. |
Verifying the Tunnel Path Metric Configuration
1.
enable
2.
show
mpls
traffic-eng
topolog
y
3.
show
mpls
traffic-eng
tunnels
4.
exit
DETAILED STEPS
Step 1 |
enable
Use this command to enable privileged EXEC mode. Enter your password if prompted. For example: Example: Router> enable Router# |
Step 2 |
show
mpls
traffic-eng
topolog
y Use the show mpls traffic-eng topology command, which displays TE and IGP metrics for each link, to verify that link metrics have been correctly configured for a network. For example: Example: Router# show mpls traffic-eng topology My_System_id: 1440.0000.0044.00 (isis level-1) IGP Id: 0090.0000.0009.00, MPLS TE Id:192.168.9.9 Router Node (isis level-1) link[0 ]:Nbr IGP Id: 0090.0000.0009.03, gen:7 frag_id 0, Intf Address:10.0.0.99 TE metric:100, IGP metric:48, attribute_flags:0x0 !!Note TE and IGP metrics physical_bw: 10000 (kbps), max_reservable_bw_global: 0 (kbps) max_reservable_bw_sub: 0 (kbps) . . . link[1 ]:Nbr IGP Id: 0055.0000.0055.00, gen:7 frag_id 0, Intf Address:10.205.0.9, Nbr Intf Address:10.205.0.55 TE metric:120, IGP metric:10, attribute_flags:0x0 !!Note TE and IGP metrics physical_bw: 155000 (kbps), max_reservable_bw_global: 500000 (kbps) max_reservable_bw_sub: 0 (kbps) . . . |
Step 3 |
show
mpls
traffic-eng
tunnels
Use the show mpls traffic-eng tunnels command, which displays the link metric used for tunnel path calculation, to verify that the desired link metrics are being used for each tunnel. For example: Example: Router# show mpls traffic-eng tunnels Name: te3640-17-c_t221 (Tunnel22) Destination: 192.168.100.22 Status: Admin: up Oper: up Path: valid Signalling: connected path option 1, type dynamic (Basis for Setup, path weight 10) Config Parameters: Bandwidth: 400 kps (Global) Priority: 1 1 Affinity: 0x0/0xFFFF Metric Type: IGP !!Note metric type AutoRoute: enabled LockDown: disabled Loadshare: 0 bw-based auto-bw: disabled(0/115) 0 Bandwidth Requested: 0 . . . Name: te3640-17-c_t222 (Tunnel33) Destination: 192.168.100.22 Status: Admin: up Oper: up Path: valid Signalling: connected path option 1, type dynamic (Basis for Setup, path weight 10) Config Parameters: Bandwidth: 200 kbps (Global) Priority: 1 1 Affinity: 0x0/0xFFFF Metric Type: TE !!Note metric type AutoRoute: enabled LockDown: disabled Loadshare: 0 bw-based auto-bw: disabled(0/115) 0 Bandwidth Requested: 0 . . . |
Step 4 |
exit
Use this command to return to user EXEC mode. For example: Example: Router# exit Router> |
Configuration Examples for Configuring a Path Calculation Metric for Tunnels
Example Configuring Link Type and Metrics for Tunnel Path Selection
The section illustrates how to configure the link metric type to be used for tunnel path selection, and how to configure the link metrics themselves. The configuration commands included focus on specifying the metric type for path calculation and assigning metrics to links. Additional commands are required to fully configure the example scenario: for example, the IGP commands for traffic engineering and the link interface commands for enabling traffic engineering and specifying available bandwidth.
The examples in this section support the simple network technology shown in the figure below.
In the figure above:
Tunnel1 and Tunnel2 run from R1 (headend) to R4 (tailend).
Tunnel3 runs from R1 to R5.
Path calculation for Tunnel1 and Tunnel3 should use a metric that represents link delay because these tunnels carry voice traffic.
Path calculation for Tunnel2 should use IGP metrics because MPLS TE carries data traffic with no delay requirement.
Configuration fragments follow for each of the routers that illustrate the configuration relating to link metrics and their use in tunnel path calculation. TE metrics that represent link delay must be configured for the network links on each of the routers, and the three tunnels must be configured on R1.
These configuration fragments force Tunnel1 to take path R1-R3-R4, Tunnel2 to take path R1-R2-R4, and Tunnel3 to take path R1-R3-R4-R5 (assuming the links have sufficient bandwidth to accommodate the tunnels).
R1 Configuration
The following example shows how to configure the tunnel headend (R1) for Tunnel1, Tunnel2, and Tunnel3 in the figure above:
interface pos0/1/0 mpls traffic-eng administrative-weight 15 !TE metric different from IGP metric interface pos0/2/0 mpls traffic-eng administrative-weight 15 !TE metric different from IGP metric interface Tunnel1 !Tunnel1 uses TE metric (default) !for path selection ip unnumbered loopback0 tunnel destination 192.168.4.4 255.255.255.0 tunnel mode mpls traffic-eng tunnel mpls traffic-eng bandwidth 1000 tunnel mpls traffic-eng path-option 1 dynamic interface Tunnel2 !Tunnel2 uses IGP metric !for path selection ip unnumbered loopback0 tunnel destination 192.168.4.4 255.255.255.0 tunnel mode mpls traffic-eng tunnel mpls traffic-eng bandwidth 1000 tunnel mpls traffic-eng path-option 1 dynamic tunnel mpls traffic-eng path-selection-metric igp !Use IGP cost for path selection. interface Tunnel3 !Tunnel3 uses TE metric (default) !for path selection ip unnumbered loopback0 tunnel destination 192.168.5.5 255.255.255.0 tunnel mode mpls traffic-eng tunnel mpls traffic-eng bandwidth 1000 tunnel mpls traffic-eng path-option 1 dynamic
R2 Configuration
The following example shows how to configure R2 in the figure above:
interface pos0/3/0 mpls traffic-eng administrative-weight 15 !TE metric different from IGP metric interface pos1/3/1 mpls traffic-eng administrative-weight 40 !TE metric different from IGP metric
R3 Configuration
The following example shows how to configure R3 in the figure above:
interface pos2/0/0 mpls traffic-eng administrative-weight 15 !TE metric different from IGP metric interface pos0/3/0 mpls traffic-eng administrative-weight 15 !TE metric different from IGP metric interface pos0/1/1 mpls traffic-eng administrative-weight 5 !TE metric different from IGP metric
R4 Configuration
The following example shows how to configure R4 in the figure above:
interface pos2/0/0 mpls traffic-eng administrative-weight 15 !TE metric different from IGP metric interface pos2/1/0 mpls traffic-eng administrative-weight 15 !TE metric different from IGP metric interface pos2/2/0 mpls traffic-eng administrative-weight 5 !TE metric different from IGP metric
R5 Configuration
The following example shows how to configure R5 in the figure above:
interface pos1/0/0 mpls traffic-eng administrative-weight 15 !TE metric different from IGP metric interface pos1/1/0 mpls traffic-eng administrative-weight 5 !TE metric different from IGP metric
Additional References
Related Documents
Related Topic |
Document Title |
---|---|
Cisco IOS commands |
|
Configuration tasks for IS-IS and OSPF |
Cisco IOS XE IP Routing Protocols Configuration Guide |
IS-IS and OSPF commands |
Cisco IOS IP Routing Protocols Command Reference |
Configuration tasks for MPLS and MPLS TE |
Cisco IOS XE Multiprotocol Label Switching Configuration Guide |
MPLS TE commands |
Cisco IOS Multiprotocol Label Switching Command Reference |
Configuration tasks for tunnels |
|
Tunnel configuration commands |
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 software releases, and feature sets, use Cisco MIB Locator found at the following URL: |
RFCs
RFC |
Title |
---|---|
No new or modified RFCs are supported by this feature, and support for existing RFCs has not been modified. |
- |
Technical Assistance
Description |
Link |
---|---|
The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password. |
Feature Information for MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels
The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Feature Name |
Releases |
Feature Information |
---|---|---|
MPLS Traffic Engineering:Configurable Path Calculation Metric for Tunnels |
12.0(18)ST 12.2(11)S 12.2(14)S 12.2(28)SB 12.4(20)T Cisco IOS XE Release 2.3 |
The MPLS Traffic Engineering - Configurable Path Calculation Metric for Tunnels feature enables the user to control the metric used in path calculation for traffic engineering (TE) tunnels on a per-tunnel basis. Certain tunnels are used to carry voice traffic, which requires low delay, and other tunnels are used to carry data. A TE link metric can be used to represent link delay and configure tunnels that carry voice traffic for path calculation and configure tunnels that carry data to use the Interior Gateway Protocol (IGP) metric for path calculation. The following commands were introduced or modified: mpls traffic-eng path-selection metric, tunnel mpls traffic-eng path-selection metric. |