Contents

Configuring error code detection· 1

About error code detection· 1

Error code detection fundamentals· 1

Interface error code detection· 1

Link quality detection· 1

Error code detection deployment 2

Restrictions and guidelines: Error code detection configuration· 2

Configuring interface error code detection· 3

Configuring link quality detection· 3

Configuring the bit error ratio calculation factors for an interface· 4

Display and maintenance commands for error code detection· 4

 

Configuring error code detection

About error code detection

As a high availability mechanism, error code detection triggers the upper-layer service module to automatically take protection actions when error code events occur. This feature reduces the influence of error codes on the service.  

Error code detection fundamentals

Interface error code detection

With this feature configured on an interface, the device periodically samples, calculates, and detects the packets received on the interface.

·     If the bit error ratio exceeds the upper threshold, an error code failure occurs on the interface. Then, an error code event is reported to trigger the upper-layer service module to take the corresponding protection action.

·     If the bit error ratio drops below the lower threshold, the error code failure is cleared on the interface. Then, an error code clearing event is reported to trigger the upper-layer service module to cancel the protection action.

Interface error code detection supports the following protection actions:

·     Trigger LSP—Error code failures on an interface can trigger LSP switchover. An error code failure occurring on an interface is reported to the upper-layer service module to switch traffic from the primary LSP to the secondary LSP. After the error code failure is cleared, traffic is switched back to the primary LSP.

·     Trigger Section—Error code failures on an interface can trigger section layer service protection. An error code failure occurring on an interface is reported to the interface management module to set the link layer protocol status of the interface to DOWN(Bit-error down). Then, the upper-layer service module associated with the interface triggers section layer service protection. After the error code failure is cleared, the link layer protocol status of the interface restores to UP and triggers the upper-layer service module to cancel section layer service protection.

Link quality detection

With this feature configured on an interface, the device periodically samples, calculates, and detects the packets received on the interface.

·     If the bit error ratio exceeds the upper threshold, an error code failure occurs on the interface. Then, the link quality of the interface becomes LOW, and an error code event is reported. In this case, IGP (for example, OSPF and IS-IS) increases the cost for the link and recalculates the routes, so that IGP does not preferentially select the link and keeps off error code failures.

·     If the bit error ratio drops below the lower threshold, the error code failure is cleared on the interface. Then, the link quality of the interface restores to GOOD, and an error code clearing event is reported. In this case, IGP restores the cost value for the interface and recalculates the routes, so that IGP can preferentially select the link again.

Error code detection deployment

In the current software version, you can deploy error code detection only on Ethernet interfaces and aggregate interfaces.

·     With this feature configured on an Ethernet interface, this feature samples, calculates, and detects the bit error ratio of the Ethernet interface, and the bit error ratio of the Ethernet interface can trigger an error code event.

·     With this feature configured on an aggregate interface, this feature samples, calculates, and detects the bit error ratios for the member ports of the aggregate interface. Interface error code detection and link quality detection are different in how to trigger error code events.

Interface error code detection deployment on an aggregate interface

An aggregate interface goes down when one of the following conditions exist:

·     Error code failures occur on all member ports of the aggregate interface.

·     The number of Selected member ports without error code failures is smaller than the minimum number of Selected member ports required for bringing up the aggregate interface.

Then, the upper-layer service module of the aggregate interface is triggered to perform the protection action.

When the number of Selected member ports without error code failures reaches the minimum number of Selected member ports required for bringing up the aggregate interface, the aggregate interface comes up, and the upper-layer service module of the aggregate interface cancels the protection action.

For more information about the minimum number of Selected member ports required for bringing up an aggregate interface, see Ethernet link aggregation configuration in Layer 2—LAN Switching Configuration Guide.

Link quality detection deployment on an aggregate interface

An aggregate interface goes down and the upper-layer service module is triggered to perform the protection action when the following conditions exist:

·     Error code failures occur on all member ports of the aggregate interface.

·     The minimum number of Selected member ports required for bringing up the aggregate interface is not configured.

The status of an aggregate interface is still up but the link quality of the aggregate interface will become LOW when the number of Selected member ports without error code failures is smaller than the minimum number of Selected member ports required for bringing up the aggregate interface. In this case, IGP (for example, OSPF and IS-IS) increases the cost for the link and recalculates the routes, so that IGP does not preferentially select the link and keeps off error code failures.

When the number of Selected member ports without error code failures reaches the minimum number of Selected member ports required for bringing up the aggregate interface, the link quality of the aggregate interface restores to GOOD. In this case, IGP restores the cost value for the interface and recalculates the routes, so that IGP can preferentially select the link again.

Restrictions and guidelines: Error code detection configuration

The interface error code detection feature and the link quality detection feature are mutually exclusive. Select a proper detection method according to the scenario.

Configuring interface error code detection

Restrictions and guidelines

The trigger-lsp keyword is not supported on a Layer 2 Ethernet or aggregate interface.

Procedure

1.     Enter system view.

system-view

2.     Enter interface view.

¡     Enter Layer 2 Ethernet interface view.

interface interface-type interface-number

¡     Enter Layer 3 Ethernet interface view.

interface interface-type interface-number

¡     Enter Layer 2 aggregate interface view.

interface bridge-aggregation interface-number

¡     Enter Layer 3 aggregate interface view.

interface route-aggregation interface-number

3.     Configure error code detection parameters for the interface.

port ifmonitor crc-error bit-error-ratio high-threshold high-value-coefficient high-value-power low-threshold low-value-coefficient low-value-power { trigger-lsp | trigger-section }

By default, no error code detection parameters are configured for an interface.

Configuring link quality detection

1.     Enter system view.

system-view

2.     Enter interface view.

¡     Enter Layer 3 Ethernet interface view.

interface interface-type interface-number

¡     Enter Layer 3 aggregate interface view.

interface route-aggregation interface-number

3.     Configure link quality detection parameters.

link-quality crc-error bit-error-ratio high-threshold high-value-coefficient high-value-power low-threshold low-value-coefficient low-value-power

By default, no link quality detection parameters are configured.

Configuring the bit error ratio calculation factors for an interface

About this task

With error code detection enabled, the device periodically samples and checks the packets sent and received by an interface and performs the following operations:

·     When the interface is in lower bit error ratio status, the device uses the upper bit error ratio calculation factor to calculate a result. Then, the device compares the calculation result with the upper bit error ratio threshold to determine whether the interface is in upper bit error ratio status.

·     When the interface is in upper bit error ratio status, the device uses the lower bit error ratio calculation factor to calculate a result. Then, the device compares the calculation result with the lower bit error ratio threshold to determine whether the interface is in lower bit error ratio status.

You can use this feature to adjust the bit error ratio calculation factors to adjust the timeliness and reliability of the calculation results. A smaller calculation factor means a higher timeliness and lower reliability.

Restrictions and guidelines

This command takes effect only when the link-quality crc-error bit-error-ratio or port ifmonitor crc-error bit-error-ratio command is executed.

Procedure

1.     Enter system view.

system-view

2.     Enter interface view.

¡     Enter Layer 2 Ethernet interface view.

interface interface-type interface-number

¡     Enter Layer 3 Ethernet interface view.

interface interface-type interface-number

¡     Enter Layer 2 aggregate interface view.

interface bridge-aggregation interface-number

¡     Enter Layer 3 aggregate interface view.

interface route-aggregation interface-number

3.     Configure the bit error ratio calculation factors for the interface.

crc-error bit-error-ratio algorithm-parameter high-factor high-factor-value low-factor low-factor-value

By default, the calculation factor is 50 for both the upper bit error ratio and lower bit error ratio.

Display and maintenance commands for error code detection

Execute display commands in any view and reset commands in user view.

 

Task	Command
Display alarm information of an interface.	display ifmonitor interface interface-type interface-number
Clear the bit error ratio status for interfaces.	reset crc-error bit-error-ratio status interface [ interface-type [ interface-number ] ]

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