ospf link-quality low incr-cost

Function

The ospf link-quality low incr-cost command enables an OSPF interface to adjust the link cost based on link quality.

The undo ospf link-quality low incr-cost command disables an OSPF interface from adjusting the link cost based on link quality.

By default, an OSPF interface cannot adjust the link cost based on link quality.

Format

ospf link-quality low incr-cost { max-reachable | cost }

undo ospf link-quality low incr-cost

Parameters

Parameter	Description	Value
max-reachable	Adjusts the link cost of an OSPF interface to the maximum link cost 65535.	-
cost	Specifies the link cost adjustment value. After you specify this parameter: If the link quality decreases, the link cost equals the original link cost plus the adjustment value. The maximum link cost allowed is 65535. If the link quality increases, the original link cost is restored.	The value is an integer ranging from 1 to 65534.
low	Configures an OSPF interface to increase the link cost when the link quality is low.	-

Parameter

Description

Value

max-reachable

Adjusts the link cost of an OSPF interface to the maximum link cost 65535.

cost

Specifies the link cost adjustment value.

After you specify this parameter:

If the link quality decreases, the link cost equals the original link cost plus the adjustment value. The maximum link cost allowed is 65535.
If the link quality increases, the original link cost is restored.

The value is an integer ranging from 1 to 65534.

low

Configures an OSPF interface to increase the link cost when the link quality is low.

Views

100GE interface view, 10GE interface view, 25GE sub-interface view, 25GE interface view, 400GE interface view, 40GE interface view, 50GE sub-interface view, 50GE interface view, Eth-Trunk interface view, FlexE interface view, GE optical interface view, GE electrical interface view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
ospf	write

Usage Guidelines

Usage Scenario

A bit error refers to the deviation between a bit that is sent and the bit that is received. Bit errors caused by optical fiber aging or optical signal jitter are inevitable on carrier networks. During data transmission, a high bit error rate will degrade or even interrupt services.

To ensure network reliability, run the ospf link-quality low incr-cost command to configure an OSPF interface to adjust the link cost based on link quality. If an OSPF interface detects that its link quality is low, the OSPF interface increases the link cost, so that its link, which has a higher bit error rate, is not used by the optimal route. After the link quality restores, the OSPF interface restores the link cost.

Prerequisites

OSPF has been enabled using the ospf enable command in the interface view.

Example

# Configure GE 0/1/0 to increase its link cost to 65535 when its link quality is low.

<HUAWEI> system-view
[~HUAWEI] interface GigabitEthernet0/1/0
[~HUAWEI-GigabitEthernet0/1/0] ospf enable area 1
[*HUAWEI-GigabitEthernet0/1/0] ospf link-quality low incr-cost max-reachable