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Cisco IOS Software Releases 12.0 S

MPLS Traffic Engineering (TE)--AutoTunnel Primary and Backup

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MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

Contents

Prerequisites for MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

Restrictions for MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

Information About MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

Overview of MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

MPLS Traffic Engineering

Backup AutoTunnels

Primary AutoTunnels

Label-Based Forwarding

Protection and Why It Is Important

How to Configure MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

Establishing MPLS Backup AutoTunnels to Protect Fast Reroutable TE LSPs

Establishing One-Hop Tunnels to All Neighbors

Configuration Examples for MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

Establishing MPLS Backup AutoTunnels to Protect Fast Reroutable TE LSPs: Example

Establishing One-Hop Tunnels to Neighbors: Example

Additional References

Related Documents

Standards

MIBs

RFCs

Technical Assistance

Command Reference

clear mpls traffic-eng auto-tunnel primary

mpls traffic-eng auto-tunnel backup

mpls traffic-eng auto-tunnel backup config

mpls traffic-eng auto-tunnel backup nhop-only

mpls traffic-eng auto-tunnel backup timers

mpls traffic-eng auto-tunnel backup tunnel-num

mpls traffic-eng auto-tunnel primary config

mpls traffic-eng auto-tunnel primary config mpls ip

mpls traffic-eng auto-tunnel primary onehop

mpls traffic-eng auto-tunnel primary timers

mpls traffic-eng auto-tunnel primary tunnel-num

show ip rsvp fast-reroute

Feature Information for MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

Glossary


MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

First Published: January 26, 2004
Last Updated: May 31, 2007

The MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup feature enables a router to dynamically build backup tunnels and to dynamically create one-hop primary tunnels on all interfaces that have been configured with Multiprotocol Label Switching (MPLS) traffic engineering (TE) tunnels.

Finding Feature Information in This Module

Your Cisco IOS software release may not support all of the features documented in this module. 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 (TE)—AutoTunnel Primary and Backup" 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 (TE)—AutoTunnel Primary and Backup

•Restrictions for MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

•Information About MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

•How to Configure MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

•Configuration Examples for MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

•Additional References

•Command Reference

•Feature Information for MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

•Glossary

Prerequisites for MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

•Configure TE on the routers.

Restrictions for MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

•You cannot enable primary one-hop autotunnels and backup autotunnels on a router that is also configured with stateful switchover (SSO) redundancy. This restriction does not prevent an MPLS TE tunnel that is automatically configured via TE AutoTunnel from being successfully recovered on a midpoint router along the LSP's path if that router experiences an SSO switchover.

Information About MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

To configure autotunnel, you need to understand the following concepts:

•Overview of MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

•MPLS Traffic Engineering

•Backup AutoTunnels

•Primary AutoTunnels

•Label-Based Forwarding

•Protection and Why It Is Important

Overview of MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup has the following features:

•Backup autotunnel—Enables a router to dynamically build backup tunnels.

•Primary one-hop autotunnel—Enables a router to dynamically create one-hop primary tunnels on all interfaces that have been configured with MPLS TE tunnels.

If no backup tunnels exist, the following types of backup tunnels are created:

•Next hop (NHOP)

•Next-next hop (NNHOP)

The MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup feature has the following benefits:

•Backup tunnels are built automatically, eliminating the need for users to preconfigure each backup tunnel and then assign the backup tunnel to the protected interface.

•The dynamic creation of one-hop primary tunnels eliminates the need to configure an MPLS TE tunnel with the Fast Reroute (FRR) option for the tunnel to be protected.

•Protection is expanded; FRR does not protect IP traffic that is not using the TE tunnel or Label Distribution Protocol (LDP) labels that are not using the TE tunnel.

MPLS Traffic Engineering

MPLS is an Internet Engineering Task Force (IETF)-specified framework that provides for the efficient designation, routing, forwarding, and switching of traffic flows through the network.

TE is the process of adjusting bandwidth allocations to ensure that enough bandwidth is left for high-priority traffic.

In MPLS TE, the upstream router creates a network tunnel for a particular traffic stream, then sets the bandwidth available for that tunnel.

Backup AutoTunnels

Without MPLS backup autotunnels, to protect a label-switched path (LSP) you had to do the following:

•Preconfigure each backup tunnel.

•Assign the backup tunnels to the protected interfaces.

An LSP requests backup protection from Resource Reservation Protocol (RSVP) FRR in the following situations:

•Receipt of the first RSVP Resv message

•Receipt of an RSVP path message with the protection attribute after the LSP has been established without the protection attribute

•Detection that a Record Route Object (RRO) changed

If there was no backup tunnel protecting the interface used by the LSP, the LSP remained unprotected.

Backup autotunnels enable a router to dynamically build backup tunnels when they are needed. This prevents you from having to build MPLS TE tunnels statically.

Backup tunnels may not be available for the following reasons:

•Static backup tunnels are not configured.

•Static backup tunnels are configured, but cannot protect the LSP. The backup tunnel may not have enough available bandwidth, the tunnel may protect a different pool, or the tunnel may be down.

If a backup tunnel is not available, the following two backup tunnels are created dynamically:

•NHOP—Protects against link failure

•NNHOP—Protects against node failure

Note At the penultimate hop, only an NHOP backup tunnel is created.

Note If two LSPs share the same output interface and NHOP, three (not four) backup tunnels are created. They share an NHOP backup tunnel.

Link Protection

Backup tunnels that bypass only a single link of the LSP's path provide link protection. They protect LSPs if a link along their path fails by rerouting the LSP's traffic to the next hop (bypassing the failed link). These are referred to as NHOP backup tunnels because they terminate at the LSP's next hop beyond the point of failure. Figure 1 illustrates an NHOP backup tunnel.

Figure 1 Next-Hop Backup Tunnel

Node Protection

Backup tunnels that bypass next-hop nodes along LSP paths are called NNHOP backup tunnels because they terminate at the node following the next-hop node of the LSPs, thereby bypassing the next-hop node. They protect LSPs by enabling the node upstream of a link or node failure to reroute the LSPs and their traffic around the failure to the next-hop node. NNHOP backup tunnels also provide protection from link failures because they bypass the failed link and the node.

Figure 2 illustrates an NNHOP backup tunnel.

Figure 2 Next-Next Hop Backup Tunnel

Explicit Paths

Explicit paths are used to create backup autotunnels as follows:

•NHOP excludes the protected link's IP address.

•NNHOP excludes the NHOP router ID.

•The explicit-path name is _auto-tunnel_tunnelxxx, where xxx matches the dynamically created backup tunnel ID.

•The interface used for the ip unnumbered command defaults to Loopback0. You can configure this to use a different interface.

Range for Backup AutoTunnels

The tunnel range for backup autotunnels is configurable. By default, the last 100 TE tunnel IDs are used; that is 65,436 to 65,535. Autotunnels detect tunnel IDs that are being used. IDs are allocated starting with the lowest number.

Foe example, if you configure a tunnel range 1000 to 1100 and statically configured TE tunnel are in that range, routers do not use those IDs. If those static tunnels are removed, the MPLS TE dynamic tunnel software can use those IDs.

Primary AutoTunnels

The MPLS Traffic Engineering AutoTunnel Primary and Backup feature enables a router to dynamically create one-hop primary tunnels on all interfaces that have been configured with MPLS traffic. The tunnels are created with zero bandwidth. The constraint-based shortest path first (CSPF) is the same as the shortest path first (SPF) when using zero bandwidth, so the router's choice of the autorouted one-hop primary tunnel is the same as if there were no tunnel. Because it is a one-hop tunnel, the encapsulation is tag-implicit (that is, there is no tag header).

Explicit Paths

Explicit paths are used to create autotunnels as follows:

•The explicit path is dynamically created.

•The explicit path includes the IP address for the interface connected to the next hop.

•The explicit-path name is _auto-tunnel_tunnelxxx, where xxx matches the dynamically created one-hop tunnel ID.

•Interfaces used for the ip unnumbered command default to Loopback0. You can configure this to use a different interface.

Range for AutoTunnels

The tunnel range is configurable. By default, the last 100 TE tunnel IDs are used; that is 65,436 to 65,535. Autotunnels detect tunnel IDs that are being used. IDs are allocated starting with the lowest number.

For example, if you configure a tunnel range 100 to 200 and statically configured TE tunnels are in that range, routers do not use those IDs. If those static tunnels are removed, the IDs become available for use by the MPLS TE dynamic tunnel software.

Label-Based Forwarding

Routers receive a packet, determine where it needs to go by examining some fields in the packet, and send it to the appropriate output device. A label is a short, fixed-length identifier that is used to forward packets. A label switching device normally replaces the label in a packet with a new value before forwarding the packet to the next hop. For this reason, the forwarding algorithm is called label swapping. A label switching device, referred to as a label switch router (LSR), runs standard IP control protocols (that is, routing protocols, RSVP, and so forth) to determine where to forward packets.

Protection and Why It Is Important

This section describes the following:

•Delivery of Packets During a Failure

•Multiple Backup Tunnels Protecting the Same Interface

•Scalability

•RSVP Hello

Delivery of Packets During a Failure

Backup tunnels that terminate at the NNHOP protect both the downstream link and node. This provides protection for link and node failures.

Multiple Backup Tunnels Protecting the Same Interface

•Redundancy—If one backup tunnel is down, other backup tunnels protect LSPs.

•Increased backup capacity—If the protected interface is a high-capacity link and no single backup path exists with an equal capacity, multiple backup tunnels can protect that one high-capacity link. The LSPs using this link will fail over to different backup tunnels, allowing all of the LSPs to have adequate bandwidth protection during failure (rerouting). If bandwidth protection is not desired, the router spreads LSPs across all available backup tunnels (that is, there is load balancing across backup tunnels).

Scalability

A backup tunnel can protect multiple LSPs. Furthermore, a backup tunnel can protect multiple interfaces. This is called many-to-one (N:1) protection. N:1 protection has significant scalability advantages over one-to-one (1:1) protection, where a separate backup tunnel must be used for each LSP needing protection.

An example of N:1 protection is that when one backup tunnel protects 5000 LSPs, each router along the backup path maintains one additional tunnel.

An example of 1:1 protection is that when 5000 backup tunnels protect 5000 LSPs, each router along the backup path must maintain state for an additional 5000 tunnels.

RSVP Hello

RSVP Hello allows a router to detect when its neighbor has gone down but its interface to that neighbor is still operational. When Layer 2 link protocols are unable to detect that the neighbor is unreachable, Hellos provide the detection mechanism; this allows the router to switch LSPs onto its backup tunnels and avoid packet loss.

How to Configure MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

This sections contains the following procedures:

•Establishing MPLS Backup AutoTunnels to Protect Fast Reroutable TE LSPs (required)

•Establishing One-Hop Tunnels to All Neighbors (required)

Establishing MPLS Backup AutoTunnels to Protect Fast Reroutable TE LSPs

To establish an MPLS backup autotunnel to protect fast reroutable TE LSPs, perform the following steps.

Note Only Steps 1 through 3 are required. If you perform additional steps, you can perform them in any order after Step 3.

SUMMARY STEPS

1. enable

2. configure terminal

3. mpls traffic-eng auto-tunnel backup

4. mpls traffic-eng auto-tunnel backup nhop-only

5. mpls traffic-eng auto-tunnel backup tunnel-num [min num] [max num]

6. mpls traffic-eng auto-tunnel backup timers removal unused sec

7. mpls traffic-eng auto-tunnel backup config unnumbered-interface interface

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 

mpls traffic-eng auto-tunnel backup

Example:

Router(config)# mpls traffic-eng auto-tunnel backup

Automatically builds NHOP and NNHOP backup tunnels.

Step 4 

mpls traffic-eng auto-tunnel backup nhop-only

Example:

Router(config)# mpls traffic-eng auto-tunnel backup nhop-only

Enables the creation of dynamic NHOP backup tunnels.

Step 5 

mpls traffic-eng auto-tunnel backup tunnel-num [min num] [max num]

Example:

Router(config)# mpls traffic-eng auto-tunnel backup tunnel-num min 1000 max 1100

Configures the range of tunnel interface numbers for backup autotunnels.

Step 6 

mpls traffic-eng auto-tunnel backup timers removal unused sec

Example:

Router(config)# mpls traffic-eng auto-tunnel backup timers removal unused 50

Configures how frequently a timer will scan backup autotunnels and remove tunnels that are not being used.

Step 7 

mpls traffic-eng auto-tunnel backup config unnumbered-interface interface

Example:

Router(config)# mpls traffic-eng auto-tunnel backup config unnumbered-interface ethernet1/0

Enables IP processing on the specified interface without an explicit address.


Establishing One-Hop Tunnels to All Neighbors

To establish one-hop tunnels to all neighbors, perform the following steps.

Note Only Steps 1 through 3 are required. If you perform additional steps, you can perform them in any order after Step 3.

SUMMARY STEPS

1. enable

2. configure terminal

3. mpls traffic-eng auto-tunnel primary onehop

4. mpls traffic-eng auto-tunnel primary tunnel-num [min num] [max num]

5. mpls traffic-eng auto-tunnel primary timers removal rerouted sec

6. mpls traffic-eng auto-tunnel primary config unnumbered interface

7. mpls traffic-eng auto-tunnel primary config mpls ip

8. clear mpls traffic-eng auto-tunnel primary

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 

mpls traffic-eng auto-tunnel primary onehop

Example:

Router(config)# mpls traffic-eng auto-tunnel primary onehop

Automatically creates primary tunnels to all next hops.

Step 4 

mpls traffic-eng auto-tunnel primary tunnel-num [min num] [max num]

Example:

Router(config)# mpls traffic-eng auto-tunnel primary tunnel-num min 2000 max 2100

Configures the range of tunnel interface numbers for primary autotunnels.

Step 5 

mpls traffic-eng auto-tunnel primary timers removal rerouted sec

Example:

Router(config)# mpls traffic-eng auto-tunnel primary timers removal rerouted 400

Configures how many seconds after a failure primary autotunnels will be removed.

Step 6 

mpls traffic-eng auto-tunnel primary config unnumbered interface

Example:

Router(config)# mpls traffic-eng auto-tunnel primary config unnumbered ethernet1/0

Enables IP processing on the specified interface without an explicit address.

Step 7 

mpls traffic-eng auto-tunnel primary config mpls ip

Example:

Router(config)# mpls traffic-eng auto-tunnel primary config mpls ip

Enables LDP on primary autotunnels.

Step 8 

clear mpls traffic-eng auto-tunnel primary

Example:

Router(config)# clear mpls traffic-eng auto-tunnel primary

Removes all primary autotunnels and re-creates them.


Configuration Examples for MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup

This section contains the following configuration examples:

•Establishing MPLS Backup AutoTunnels to Protect Fast Reroutable TE LSPs: Example

•Establishing One-Hop Tunnels to Neighbors: Example

Establishing MPLS Backup AutoTunnels to Protect Fast Reroutable TE LSPs: Example

Note This example does not include the mpls traffic-eng auto-tunnel backup nhop-only command because AutoTunnel would not be able to create any backup tunnels.

To determine if there are any backup tunnels, enter the show ip rsvp fast-reroute command. This example shows that there is a static configured primary tunnel and no backup tunnels. For a description of the command output fields, refer to the "show ip rsvp fast-reroute" section. 

Router(config)# show ip rsvp fast-reroute


Primary     Protect   BW         Backup 

Tunnel      I/F       BPS:Type   Tunnel:Label  State  Level   Type 

------      -------   -------    ------------  ------ -----   ---- 

R3-PRP_t0   PO3/1     0:G        None          None   None

The following command causes AutoTunnel to automatically configure NHOP and NNHOP backup tunnels: 

Router(config)# mpls traffic-eng auto-tunnel backup

As illustrated in the show ip interface brief command output, AutoTunnel created two backup tunnels that have tunnel IDs 65436 and 65437: 

Router# show ip interface brief 


Interface              IP-Address      OK? Method Status                  Protocol 

POS2/0                 10.0.0.14       YES NVRAM  down                    down 

POS2/1                 10.0.0.49       YES NVRAM  up                      up 

POS2/2                 10.0.0.45       YES NVRAM  up                      up 

POS2/3                 10.0.0.57       YES NVRAM  administratively down   down 

POS3/0                 10.0.0.18       YES NVRAM  down                    down 

POS3/1                 10.0.0.33       YES NVRAM  up                      up 

POS3/2                 unassigned      YES NVRAM  administratively down   down 

POS3/3                 unassigned      YES NVRAM  administratively down   down 

GigabitEthernet4/0     10.0.0.37       YES NVRAM  up                      up 

GigabitEthernet4/1     unassigned      YES NVRAM  administratively down   down 

GigabitEthernet4/2     unassigned      YES NVRAM  administratively down   down 

Loopback0              10.0.3.1        YES NVRAM  up                      up 

Tunnel0                10.0.3.1        YES unset  up                      up       

Tunnel65436            10.0.3.1        YES unset  up                      up 

Tunnel65437            10.0.3.1        YES unset  up                      up 

Ethernet0              10.3.38.3       YES NVRAM  up                      up 

Ethernet1              unassigned      YES NVRAM  administratively down   down 

R3-PRP#

The following command prevents AutoTunnel from creating NNHOP backup tunnels: 

Router# mpls traffic-eng auto-tunnel backup nhop-only

The "Type" field in the following show ip rsvp fast-reroute command shows that there is only an NHOP tunnel: 

Router# show ip rsvp fast-reroute 


Primary    Protect  BW Backup 

Tunnel     I/F      BPS:Type  Tunnel:Label  State  Level   Type 

------     -------  --------  ------------- ------ ------- ---- 

R3-PRP_t0  PO3/1    0:G       Tu65436:24    Ready  any-unl Nhop

The following command changes the minimum and maximum tunnel interface numbers to 1000 and 1100, respectively: 

Router# mpls traffic-eng auto-tunnel backup tunnel-num min 1000 max 1100

You can verify the ID numbers and autotunnel backup range ID by entering the show ip rsvp fast-reroute and show ip interface brief commands. In this example, only one backup tunnel is protecting the primary tunnel: 

Router# show ip rsvp fast-reroute 


Primary                   Protect BW         Backup 

Tunnel                    I/F     BPS:Type   Tunnel:Label  State  Level   Type 

------                    ------- --------   ------------- ------ -----   ------ 

R3-PRP_t0                 PO3/1   0:G        Tu1000:24     Ready  any-unl Nhop 


Router# show ip interface brief 


Interface            IP-Address    OK?  Method  Status                  Protocol 

POS2/0               10.0.0.14     YES  NVRAM   down                    down 

POS2/1               10.0.0.49     YES  NVRAM   up                      up 

POS2/2               10.0.0.45     YES  NVRAM   up                      up 

POS2/3               10.0.0.57     YES  NVRAM   administratively down   down 

POS3/0               10.0.0.18     YES  NVRAM   down                    down 

POS3/1               10.0.0.33     YES  NVRAM   up                      up 

POS3/2               unassigned    YES  NVRAM   administratively down   down 

POS3/3               unassigned    YES  NVRAM   administratively down   down 

GigabitEthernet4/0   10.0.0.37     YES  NVRAM   up                      up 

GigabitEthernet4/1   unassigned    YES  NVRAM   administratively down   down 

GigabitEthernet4/2   unassigned    YES  NVRAM   administratively down   down 

Loopback0            10.0.3.1      YES  NVRAM   up                      up 

Tunnel0              10.0.3.1      YES  unset   up                      up 

Tunnel65436          10.0.3.1      YES  unset   up                      up 

Ethernet0            10.3.38.3     YES  NVRAM   up                      up 

Ethernet1            unassigned    YES  NVRAM   administratively down   down

The default tunnel range for autotunnel backup tunnels is 65,436 through 65,535. The following show ip rsvp fast-reroute command changes the tunnel range IDs: 

Router# show ip rsvp fast-reroute 


Primary     Protect  BW         Backup 

Tunnel       I/F     BPS:Type   Tunnel:Label   State   Level    Type 

------      -------  --------   ------------- ------   -----    ------ 

R3-PRP_t0   PO3/1    0:G        Tu1001:0       Ready   any-unl  N-Nhop

The results are shown in the show ip interface brief command: 

Router# show ip interface 

Router# show ip interface brief

Interface              UP-Address   OK?  Method  Status                 Protocol

POS2/0                 10.0.0.14    YES  NVRAM   down                   down 

POS2/1                 10.0.0.49    YES  NVRAM   up                     up 

POS2/2                 10.0.0.45    YES  NVRAM   up                     up 

POS2/3                 10.0.0.57    YES  NVRAM   up                     up 

POS3/0                 10.0.0.18    YES  NVRAM   up                     up 

POS3/1                 10.0.0.33    YES  NVRAM   up                     up 

POS3/2                 unassigned   YES  NVRAM   administratively down  down 

POS3/3                 unassigned   YES  NVRAM   administratively down  down 

Loopback0              10.0.3.1     YES  NVRAM   up                     up 

Tunnel0                10.0.3.1     YES  unset   up                     up 

Tunnel1000             10.0.3.1     YES  unset   up                     up 

Tunnel1001             10.0.3.1     YES  unset   up                     up 

Ethernet0              10.3.38.3     YES  NVRAM   up                     up 

Ethernet1              unassigned   YES  NVRAM   administratively down  down

The following mpls traffic-eng auto-tunnel backup timers removal unused command specifies that a timer will scan backup autotunnels every 50 seconds and the timer will remove tunnels that are not being used: 

Router(config)# mpls traffic-eng auto-tunnel backup timers removal unused 50

The following mpls traffic-eng auto-tunnel backup config unnumbered-interface command enables IP processing on interface POS3/1: 

Router(config)# mpls traffic-eng auto-tunnel backup config unnumbered-interface POS3/1

To verify that IP processing is enabled on POS3/1, enter the show interfaces tunnel command: 

Router# show interfaces tunnel 1001 


Tunnel1001 is up, line protocol is up 

  Hardware is Tunnel 

  Interface is unnumbered.  Using address of POS3/1 (10.0.0.33) 

  MTU 1514 bytes, BW 9 Kbit, DLY 500000 usec, rely 255/255, load 1/255 

  Encapsulation TUNNEL, loopback not set 

  Keepalive not set 

  Tunnel source 10.0.0.0, destination 10.0.5.1 

  Tunnel protocol/transport Label Switching, sequencing disabled 

  Key disabled 

  Checksumming of packets disabled 

  Last input never, output never, output hang never 

  Last clearing of "show interface" counters never 

  Queueing strategy: fifo 

  Output queue 0/0, 0 drops; input queue 0/75, 0 drops 

  5 minute input rate 0 bits/sec, 0 packets/sec 

  5 minute output rate 0 bits/sec, 0 packets/sec 

     0 packets input, 0 bytes, 0 no buffer 

     Received 0 broadcasts, 0 runts, 0 giants, 0 throttles 

     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort 

     0 packets output, 0 bytes, 0 underruns 

     0 output errors, 0 collisions, 0 interface resets 

     0 output buffer failures, 0 output buffers swapped out

Establishing One-Hop Tunnels to Neighbors: Example

For AutoTunnel to automatically create primary tunnels to all next hops, you must enter the following command: 

Router(config)# mpls traffic-eng auto-tunnel primary onehop

In this example there are four primary tunnels and no backup tunnels. To verify that configuration, enter the show ip rsvp fast-reroute command and the show ip interface brief command: 

Router# show ip rsvp fast-reroute


Primary                   Protect BW         Backup 

Tunnel                    I/F     BPS:Type   Tunnel:Label  State  Level   Type 

------                    ------- --------   ------------- ------ -----   ------ 

R3-PRP_t65337             PO2/2   0:G        None          None   None 

R3-PRP_t65338             PO3/1   0:G        None          None   None 

R3-PRP_t65339             Gi4/0   0:G        None          None   None 

R3-PRP_t65336             PO2/1   0:G        None          None   None 


Router# show ip interface brief


Interface              IP-Address    OK?  Method Status                 Protocol 

POS2/0                 10.0.0.14     YES  NVRAM  down                   down 

POS2/1                 10.0.0.49     YES  NVRAM  up                     up 

POS2/2                 10.0.0.45     YES  NVRAM  up                     up 

POS2/3                 10.0.0.57     YES  NVRAM  administratively down  down 

POS3/0                 10.0.0.18     YES  NVRAM  down                   down 

POS3/1                 10.0.0.33     YES  NVRAM  up                     up 

POS3/2                 unassigned    YES  NVRAM  administratively down  down 

POS3/3                 unassigned    YES  NVRAM  administratively down  down 

GigabitEthernet4/0     10.0.0.37     YES  NVRAM  up                     up 

GigabitEthernet4/1     unassigned    YES  NVRAM  administratively down  down 

GigabitEthernet4/2     unassigned    YES  NVRAM  administratively down  down 

Loopback0              10.0.3.1      YES  NVRAM  up                     up 

Tunnel0                10.0.3.1      YES  unset  administratively down  down 

Tunnel65336            10.0.3.1      YES  unset  up                     up 

Tunnel65337            10.0.3.1      YES  unset  up                     up 

Tunnel65338            10.0.3.1      YES  unset  up                     up 

Tunnel65339            10.0.3.1      YES  unset  up                     up 

Ethernet0              10.3.38.3     YES  NVRAM  up                     up 

Ethernet1              unassigned    YES  NVRAM  administratively down  down 

R3-PRP#

The default tunnel range for primary autotunnels is 65,336 through 65,435. The following mpls traffic-eng auto-tunnel primary tunnel-num command changes the range to 2000 through 2100: 

Router(config)# mpls traffic-eng auto-tunnel primary tunnel-num min 2000 max 2100

The following sample output from the show ip rsvp fast-reroute command and the show ip interface brief command shows that the tunnel IDs are 2000, 2001, 2002, and 2003: 

Router# show ip rsvp fast-reroute 


Primary                   Protect BW         Backup 

Tunnel                    I/F     BPS:Type   Tunnel:Label  State  Level   Type 

------                    ------- --------   ------------- ------ -----   ------ 

R3-PRP_t2001              PO2/2   0:G        None          None   None 

R3-PRP_t2002              PO3/1   0:G        None          None   None 

R3-PRP_t2003              Gi4/0   0:G        None          None   None 

R3-PRP_t2000              PO2/1   0:G        None          None   None 


Router# show ip interface brief 


Interface              IP-Address      OK? Method Status                Protocol 

POS2/0                 10.0.0.14       YES NVRAM  down                  down 

POS2/1                 10.0.0.49       YES NVRAM  up                    up 

POS2/2                 10.0.0.45       YES NVRAM  up                    up 

POS2/3                 10.0.0.57       YES NVRAM  administratively down down 

POS3/0                 10.0.0.18       YES NVRAM  down                  down 

POS3/1                 10.0.0.33       YES NVRAM  up                    up 

POS3/2                 unassigned      YES NVRAM  administratively down down 

POS3/3                 unassigned      YES NVRAM  administratively down down 

GigabitEthernet4/0     10.0.0.37       YES NVRAM  up                    up 

GigabitEthernet4/1     unassigned      YES NVRAM  administratively down down 

GigabitEthernet4/2     unassigned      YES NVRAM  administratively down down 

Loopback0              10.0.3.1        YES NVRAM  up                    up 

Tunnel0                10.0.3.1        YES unset  administratively down down 

Tunnel2000             10.0.3.1        YES unset  up                    up 

Tunnel2001             10.0.3.1        YES unset  up                    up 

Tunnel2002             10.0.3.1        YES unset  up                    up 

Tunnel2003             10.0.3.1        YES unset  up                    up 

Ethernet0              10.3.38.3 '     YES NVRAM  up                    up 

Ethernet1              unassigned      YES NVRAM  administratively down down

The following mpls traffic-eng auto-tunnel primary timers command specifies that a timer will scan backup autotunnels every 50 seconds and remove tunnels that are not being used: 

Router(config)# mpls traffic-eng auto-tunnel primary timers removal rerouted 50

The following mpls traffic-eng auto-tunnel primary config unnumbered command enables IP processing on interface POS3/1: 

Router(config)# mpls traffic-eng auto-tunnel primary config unnumbered POS3/1

To specify that AutoTunnel remove all primary autotunnels and re-create them, enter the following command: 

Router(config)# clear mpls traffic-eng auto-tunnel primary

Additional References

The following sections provide references related to the MPLS Traffic Engineering (TE)—AutoTunnel Primary and Backup feature.

Related Documents


Standards

Standards
Title

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

—


MIBs

MIBs
MIBs Link

No new or modified MIBs are supported by this release 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

RFCs
Title

No new or modified RFCs are supported by this release 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. Access to most tools on the Cisco Support website requires a Cisco.com user ID and password. If you have a valid service contract but do not have a user ID or password, you can register on Cisco.com.

http://www.cisco.com/techsupport


Command Reference

This section documents only commands that are new or modified.

•clear mpls traffic-eng auto-tunnel primary

•mpls traffic-eng auto-tunnel backup

•mpls traffic-eng auto-tunnel backup config

•mpls traffic-eng auto-tunnel backup nhop-only

•mpls traffic-eng auto-tunnel backup timers

•mpls traffic-eng auto-tunnel backup tunnel-num

•mpls traffic-eng auto-tunnel primary config

•mpls traffic-eng auto-tunnel primary config mpls ip

•mpls traffic-eng auto-tunnel primary onehop

•mpls traffic-eng auto-tunnel primary timers

•mpls traffic-eng auto-tunnel primary tunnel-num

•show ip rsvp fast-reroute

clear mpls traffic-eng auto-tunnel primary

To remove all the primary autotunnels and re-create them, use the clear mpls traffic-eng auto-tunnel primary command in global configuration mode.

clear mpls traffic-eng auto-tunnel primary

Syntax Description

This command has no arguments or keywords.

Command Default

None

Command Modes

Global configuration

Command History

Release
Modification

12.0(27)S

This command was introduced.

12.2(33)SRA

This command was integrated into Cisco IOS Release 12.2(33)SRA.

12.2(33)SXH

This command was integrated into Cisco IOS Release 12.2(33)SXH.


Examples

The following example removes all primary autotunnels and re-creates them: 

Router# clear mpls traffic-eng auto-tunnel primary

Related Commands

Command
Description

show ip rsvp fast-reroute

Displays information about fast reroutable primary tunnels and their corresponding backup tunnels that provide protection.


mpls traffic-eng auto-tunnel backup

To automatically build next-hop (NHOP) and next-next hop (NNHOP) backup tunnels, use the mpls traffic-eng auto-tunnel backup command in global configuration mode. To delete the NHOP and NNHOP backup tunnels, use the no form of this command.

mpls traffic-eng auto-tunnel backup

no mpls traffic-eng auto-tunnel backup

Syntax Description

This command has no arguments or keywords.

Command Default

None

Command Modes

Global configuration

Command History

Release
Modification

12.0(27)S

This command was introduced.

12.2(33)SRA

This command was integrated into Cisco IOS Release 12.2(33)SRA.

12.2(33)SXH

This command was integrated into Cisco IOS Release 12.2(33)SXH.


Usage Guidelines

The no form of this command deletes both NHOP and NNHOP backup tunnels that were configured using either the mpls traffic-eng auto-tunnel backup command or the mpls traffic-eng auto-tunnel backup nhop-only command.

Examples

The following example automatically builds NHOP and NNHOP backup tunnels: 

Router# mpls traffic-eng auto-tunnel backup

Related Commands

Command
Description

mpls traffic-eng auto-tunnel backup config

Enables IP processing without an explicit address.

mpls traffic-eng auto-tunnel backup nhop-only

Enables the creation of only dynamic next-hop backup tunnels.

mpls traffic-eng auto-tunnel backup timers

Configures how frequently a timer will scan backup autotunnels and remove tunnels that are not being used.

mpls traffic-eng auto-tunnel backup tunnel-num

Configures the range of tunnel interface numbers for backup autotunnels.


mpls traffic-eng auto-tunnel backup config

To enable IP processing without an explicit address, use the mpls traffic-eng auto-tunnel backup config command in global configuration mode. To disable IP processing without an explicit address, use the no form of this command.

mpls traffic-eng auto-tunnel backup config unnumbered-interface interface

no mpls traffic-eng auto-tunnel backup config unnumbered-interface interface

Syntax Description

unnumbered-interface interface

Interface on which IP processing will be enabled without an explicit address. Default: Loopback0.


Command Default

None

Command Modes

Global configuration

Command History

Release
Modification

12.0(27)S

This command was introduced.

12.2(33)SRA

This command was integrated into Cisco IOS Release 12.2(33)SRA.

12.2(33)SXH

This command was integrated into Cisco IOS Release 12.2(33)SXH.


Examples

The following example enables IP processing on an Ethernet interface without an explicit address: 

Router# mpls traffic-eng auto-tunnel backup config unnumbered-interface ethernet1/0

Related Commands

Command
Description

mpls traffic-eng auto-tunnel backup

Automatically builds NHOP and NNHOP backup tunnels.

mpls traffic-eng auto-tunnel backup nhop-only

Enables the creation of only dynamic next-hop backup tunnels.

mpls traffic-eng auto-tunnel backup timers

Configures how frequently a timer will scan backup autotunnels and remove tunnels that are not currently being used.

mpls traffic-eng auto-tunnel backup tunnel-num

Configures the range of tunnel interface numbers for backup autotunnels.


mpls traffic-eng auto-tunnel backup nhop-only

To automatically build next-hop (NHOP) backup tunnels, use the mpls traffic-eng auto-tunnel backup nhop-only command in global configuration mode. To delete the NHOP backup tunnels, use the no form of this command.

mpls traffic-eng auto-tunnel backup nhop-only

no mpls traffic-eng auto-tunnel backup nhop-only

Syntax Description

This command has no arguments or keywords.

Command Default

The dynamically created backup tunnel uses Loopback0.

Command Modes

Global configuration

Command History

Release
Modification

12.0(27)S

This command was introduced.

12.2(33)SRA

This command was integrated into Cisco IOS Release 12.2(33)SRA.

12.2(33)SXH

This command was integrated into Cisco IOS Release 12.2(33)SXH.


Usage Guidelines

This command permits the creation of only NHOP backup tunnels; next-next hop (NNHOP) backup tunnels are not created. The no form of this command deletes only the NHOP backup tunnels; NNHOP backup tunnels are not deleted.

Examples

The following example enables the creation of only dynamic NHOP backup tunnels: 

Router# mpls traffic-eng auto-tunnel backup nhop-only

Related Commands

Command
Description

mpls traffic-eng auto-tunnel backup

Automatically builds NHOP and NNHOP backup tunnels.

mpls traffic-eng auto-tunnel backup config

Enables IP processing without an explicit address.

mpls traffic-eng auto-tunnel backup timers

Configures how frequently a timer will scan backup autotunnels and remove tunnels that are not being used.

mpls traffic-eng auto-tunnel backup tunnel-num

Configures the range of tunnel interface numbers for backup autotunnels.


mpls traffic-eng auto-tunnel backup timers

To configure how frequently a timer will scan backup autotunnels and remove tunnels that are not being used, use the mpls traffic-eng auto-tunnel backup timers command in global configuration mode. To disable this configuration, use the no form of this command.

mpls traffic-eng auto-tunnel backup timers removal unused [sec]

no mpls traffic-eng auto-tunnel backup timers removal unused [sec]

Syntax Description

removal unused sec

Configures how frequently (in seconds) a timer will scan the backup autotunnels and remove tunnels that are not being used. Valid values are 0 to 604,800.


Command Default

The timer scans backup autotunnels and removes tunnels that are not being used every 3600 seconds (60 minutes).

Command Modes

Global configuration

Command History

Release
Modification

12.0(27)S

This command was introduced.

12.2(33)SRA

This command was integrated into Cisco IOS Release 12.2(33)SRA.

12.2(33)SXH

This command was integrated into Cisco IOS Release 12.2(33)SXH.


Examples

The following example shows that a timer will scan backup autotunnels every 80 seconds and remove tunnels that are not being used: 

Router# mpls traffic-eng auto-tunnel backup timers removal unused 80

Related Commands

Command
Description

mpls traffic-eng auto-tunnel backup

Automatically builds NHOP and NNHOP backup tunnels.

mpls traffic-eng auto-tunnel backup config

Enables IP processing without an explicit address.

mpls traffic-eng auto-tunnel backup nhop-only

Enables the creation of only dynamic next-hop backup tunnels.

mpls traffic-eng auto-tunnel backup tunnel-num

Configures the range of tunnel interface numbers for backup autotunnels.


mpls traffic-eng auto-tunnel backup tunnel-num

To configure the range of tunnel interface numbers for backup autotunnels, use the mpls traffic-eng auto-tunnel backup tunnel-num command in global configuration mode. To disable this configuration, use the no form of this command.

mpls traffic-eng auto-tunnel backup tunnel-num [min num] [max num]

no mpls traffic-eng auto-tunnel backup tunnel-num [min num] [max num]

Syntax Description

min num

(Optional) Minimum number of the backup tunnels. Valid values are from 0 to 65535. Default: 65436.

max num

(Optional) Maximum number of the backup tunnels. Valid values are from 0 to 65535. Default: 65535.


Command Default

None

Command Modes

Global configuration

Command History

Release
Modification

12.0(27)S

This command was introduced.

12.2(33)SRA

This command was integrated into Cisco IOS Release 12.2(33)SRA.

12.2(33)SXH

This command was integrated into Cisco IOS Release 12.2(33)SXH.


Examples

The following example configures the range of backup autotunnel numbers to be between 1000 and 1100: 

Router# mpls traffic-eng auto-tunnel backup tunnel-num min 1000 max 1100

Related Commands

Command
Description

mpls traffic-eng auto-tunnel backup

Automatically builds NHOP and NNHOP backup tunnels.

mpls traffic-eng auto-tunnel backup config

Enables IP processing without an explicit address.

mpls traffic-eng auto-tunnel backup nhop-only

Enables the creation of only dynamic next-hop backup tunn