metric

---

Defines the metric for this tunnel or path list.

Syntax: [no] metric [absolute | relative] [+ | -] {0...2147483647}

absolute	Identifies the specified metric value as a fixed value.
relative	Identifies the specified metric value as a relative value. The actual metric applied to this tunnel is the TE metric minus or plus the specified value.
+	Specifies that the relative metric value for this tunnel is calculated by adding the specified value to the TE metric.
-	Specifies that the relative metric value for this tunnel is calculated by subtracting the specified value from the TE metric.
0...2147483647	Valid values for the metric. For absolute metrics: specifies the absolute metric. This value must be greater than 0. If a value of 0 or less is entered, the metric is set to 1. For relative metrics: specifies the value that is added or subtracted to the TE metric.

Description: There are three classes of metrics:

• The IGP metric is used by the IGP.
  
  
• The TE metric is used to decide which way the tunnel goes.
  
  
• The tunnel metric sets a relative preference between this tunnel and other routes. The tunnel metric is computed relative to the TE metric or is configured as an absolute value.
  
  

The metric command sets the tunnel metric for the tunnel. The metric value represents a cost; higher cost equates to less preference. There are two types of tunnel metric: absolute and relative.

An absolute tunnel metric is a fixed value that does not take into consideration the topology of the network. This fixed metric sets the cost of IP routes advertised by the tunnel egress router, and of all routes downstream of the tunnel egress router.

A relative tunnel metric is a negative or positive adjustment of the dynamic TE metric as calculated by the SPF computation. If a tunnel had an TE calculated cost of 20 and was assigned a metric relative value of -5, then the metric cost of the tunnel would be 15, with all costs of routers downstream of the tunnel added to that value.

If the destination for a traffic flow is attached to the egress LSR, TE selects the tunnel with the lowest tunnel metric. If the destination is not the egress LSR, the tunnel metric is added to the IGP metric, and TE selects the lowest cost path based on the combined value.

If no metric is explicitly configured, the default is to use a relative metric with a value of 0.

Use the metric absolute n command to define an absolute metric with the value of n.

Use the metric relative + n command to define a relative metric where the specified value n is added to the TE metric.

Use the metric relative - n command to define a relative metric where the specified value n is subtracted from the TE metric.

Use the no metric command to delete the metric

Factory Default: Relative metric of 0.

Command mode: Traffic engineering parameter-set, tunnel-default, and traffic engineering tunnel-name.

Example 1: In the following example, the metric relative command sets the metric as 3 greater than the TE metric:

Enter configuration commands, one per line. End with CNTL/Z. router(config)#mpls te ospf router(config-te)#tunnel ToPVE router(config-te-tunnel)#metric relative +3

Example 2: In the following example, the metric absolute command sets the metric as 45:

Enter configuration commands, one per line. End with CNTL/Z. router(config)#mpls te ospf router(config-te)#tunnel ToPVE router(config-te-tunnel)#metric absolute 45

Related Commands: tunnel
tunnel default
tunnel parameter-set

Copyright © 2004 Avici Systems Inc.
Avici® and TSR® is a registered trademark of Avici Systems Inc.
IPriori™, Composite Links™, SSR™, QSR, and NSR® are trademarks of Avici Systems Inc.

   Source File Name: TE%20Commands.fm
    HTML File Name: TE%20Commands31.html
    Last Updated: 12/19/04 at 14:56:07

Please email suggestions and comments to: doc@avici.com