Build MPLS-TE Topology and Tunnels: Example, on page 342
MPLS Traffic Engineering
Multiprotocol Label Switching (MPLS) is an Internet Engineering Task Force (IETF)-specified framework
that provides 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 available for
high-priority traffic.
In MPLS TE, the upstream router creates a network tunnel for a particular traffic stream and sets the bandwidth
available for that tunnel.
Backup AutoTunnels
The MPLS Traffic Engineering AutoTunnel Backup feature enables a router to dynamically build backup
tunnels on the interfaces that are configured with MPLS TE tunnels. This feature enables a router to dynamically
build backup tunnels when they are needed. This prevents you from having to build MPLS TE tunnels
statically
.
The MPLS Traffic Engineering (TE)
—
AutoTunnel Backup feature has these 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.
•
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.
This feature protects against these failures:
•
P2P Tunnel NHOP protection
—
Protects against link failure for the associated P2P protected tunnel
•
P2P Tunnel NNHOP protection
—
Protects against node failure for the associated P2P protected tunnel
•
P2MP Tunnel NHOP protection
—
Protects against link failure for the associated P2MP protected
tunnel
Related Topics
Enabling an AutoTunnel Backup, on page 225
Removing an AutoTunnel Backup, on page 226
Establishing MPLS Backup AutoTunnels to Protect Fast Reroutable TE LSPs, on page 227
Establishing Next-Hop Tunnels with Link Protection, on page 229
Configure the MPLS-TE Auto-Tunnel Backup: Example, on page 356
AutoTunnel Attribute-set
This feature supports auto-tunnels configuration using attribute templates, known as attribute-set. The TE
attribute-set template that specifies a set of TE tunnel attributes, is locally configured at the head-end of
auto-tunnels. The control plane triggers the automatic provisioning of a corresponding TE tunnel, whose
characteristics are specified in the respective attribute-set.
Currently, auto-tunnel backups are created with the default values of all tunnel attributes. To support
configurable attributes for auto-tunnel backup, it is required to configure attribute-set and assign it to the
Cisco IOS XR MPLS Configuration Guide for the Cisco CRS Router, Release 5.1.x
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Implementing MPLS Traffic Engineering
MPLS Traffic Engineering