Path Option Attributes; Configuration Hierarchy Of Path Option Attributes - Cisco CRS Configuration Manual

Path Option Attributes

Related Topics
Enabling Soft-Preemption on a Node, on page 319
Enabling Soft-Preemption on a Tunnel, on page 320
Path Option Attributes
The path option attributes are configurable through a template configuration. This template, named attribute-set,
is configured globally in the MPLS traffic-engineering mode.
You can apply an attribute-set to a path option on a per-LSP basis. The path option configuration is extended
to take a path option attribute name. LSPs computed with a particular path option uses the attributes as specified
by the attribute-set under that path option.
These prerequisites are required to implement path option attributes:
• Path option type attribute-set is configured in the MPLS TE mode
• Path option CLI extended to accept an attribute-set name
The signalled-bandwidth and affinity attributes are supported under the attribute-set template.
Note
Related Topics
Configuring Attributes within a Path-Option Attribute, on page 322

Configuration Hierarchy of Path Option Attributes

You can specify a value for an attribute within a path option attribute-set template. This does not prevent
the configuring of the same attribute at a tunnel level. However, it is important to note that only one level is
taken into account. So, the configuration at the LSP level is considered more specific than the one at the level
of the tunnel, and it is used from this point onwards.
Attributes that are not specified within an attribute-set take their values as usual--configuration at the tunnel
level, configuration at the global MPLS level, or default values. Here is an example:
attribute-set path-option MYSET
affinity 0xBEEF mask 0xBEEF
interface tunnel-te 10
affinity 0xCAFE mask 0xCAFE
signalled-bandwidth 1000
path-option 1 dynamic attribute-set name MYSET
path-option 2 dynamic
In this example, the attribute-set named MYSET is specifying affinity as 0xBEEF. The signalled bandwidth
has not been configured in this MYSET. The tunnel 10, meanwhile, has affinity 0xCAFE configured. LSPs
computed from path-option 1 uses the affinity 0xBEEF/0xBEEF, while LSPs computed from path-option 2
uses the affinity 0xCAFE/0xCAFE. All LSPs computed using any of these path-options use
signalled-bandwidth as 1000, as this is the only value that is specified only at the tunnel level.
Cisco IOS XR MPLS Configuration Guide for the Cisco CRS Router, Release 5.1.x
204
Implementing MPLS Traffic Engineering