apply cost

Function

The apply cost command sets the MED value for BGP routes or cost value for routes of other protocols.

The undo apply cost command cancels the configuration.

By default, no MED value is set for BGP routes nor cost value is set for routes of other protocols.

Format

apply cost [ + | - ] cost

apply cost inherit

apply cost none

undo apply cost

Parameters

Parameter	Description	Value
+	Increases the route cost. If the link quality is poor or the link bandwidth is low, specify this parameter to increase the route cost, which helps control route selection.	If the MED of BGP routes or cost of non-BGP routes is greater than the maximum value (4294967295) after the adjustment, 4294967295 takes effect.
-	Reduces the route cost. If the link quality is good or the link bandwidth is high, specify this parameter to reduce the route cost, which helps control route selection.	If the MED of BGP routes or cost of non-BGP routes is less than the minimum value (0) after the adjustment, 0 takes effect.
cost	Specifies the route cost. To control route selection, adjust the route cost to prevent routing loops.	The value is an integer ranging from 0 to 4294967295.
inherit	Inherits the original route cost. This function applies to IGP routes, not to BGP routes.	-
none	Delete the MED value of BGP routes.	-

Views

Route-policy view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
route-base	write

Usage Guidelines

Usage Scenario

When the filtering conditions specified in if-match clauses are met, you can run the apply cost command to change the route cost, which helps control route selection. After setting the cost of the routes that match the route-policy, the cost of the imported routes is changed accordingly.

Run the route-policy command to enter the route-policy view.
A route-policy may consist of multiple nodes. The relationship between the nodes is "OR". The system matches a route against the nodes in sequence. If the route matches a node, the route matches the route-policy, and the system no longer matches it against other nodes.
Each node comprises a set of if-match and apply clauses. The if-match clauses define the filtering rules that are used to match certain route attributes. The relationship among if-match clauses of the same node that are based on different route attributes is AND. A route matches a node only when the route matches all the filtering rules specified in the if-match clauses of the node. The apply clauses specify actions. The relationship among if-match clauses of the same node that are based on the same route attribute is OR. The system matches routes against the if-match clauses in order. If a route matches an if-match clause, the system no longer matches the route against the rest if-match clauses. For example, the if-match community-filter 1 and if-match as-path-filter 1 configurations in node 10 are based on different route attributes. Therefore, the relationship among if-match clauses of this node is AND. The if-match community-filter 1 and if-match community-filter 2 configurations in node 20 are both based on the community attribute. Therefore, the relationship among if-match clauses of this node is OR. The apply clauses specify actions. If a route matches a node, the apply clauses set some attributes for the route.
By default, the route cost is not set.
After the undo apply cost command is run to cancel the set route cost, the cost of the imported routes is not affected by the route-policy.

Prerequisites

A route-policy has been configured using the route-policy command.

Configuration Impact

After routes match the route-policy, the cost of the routes is changed.

Precautions

The costs of imported routes are independent of the route-policy after the undo apply cost command is used to cancel the configuration of route costs.

Example

# Define an apply clause to set the route cost to 120.

<HUAWEI> system-view
[~HUAWEI] route-policy policy permit node 10
[*HUAWEI-route-policy] apply cost 120