No relevant resource is found in the selected language.

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies. Read our privacy policy>Search


To have a better experience, please upgrade your IE browser.


CX11x, CX31x, CX710 (Earlier Than V6.03), and CX91x Series Switch Modules V100R001C10 Configuration Guide 12

The documents describe the configuration of various services supported by the CX11x&CX31x&CX91x series switch modules The description covers configuration examples and function configurations.
Rate and give feedback:
Huawei uses machine translation combined with human proofreading to translate this document to different languages in order to help you better understand the content of this document. Note: Even the most advanced machine translation cannot match the quality of professional translators. Huawei shall not bear any responsibility for translation accuracy and it is recommended that you refer to the English document (a link for which has been provided).
Configuration Task Summary

Configuration Task Summary

After basic OSPF functions are configured, you can build a basic OSPF network. If other OSPF functions are required, configure them according to reference sections.

Table 7-28 describes the OSPF configuration tasks.

Table 7-28 OSPF configuration tasks




Configuring Basic OSPF Functions

The configuration of basic OSPF functions is the foundation of the OSPF network construction and the precondition for other OSPF functions.

Configuring Basic OSPF Functions

Setting Parameters for OSPF Neighbor Relationship

Configuring OSPF Attributes in Different Types of Networks

Configuring OSPF Areas

  • In a stub area, the area border router (ABR) does not transmit learned autonomous system (AS) external routes. This implementation reduces entries in the routing tables on ABRs in stub areas and the amount of routing information to be transmitted.

  • An NSSA is a new type of OSPF area. Neither the NSSA nor the stub area transmits routes learned from other areas in the AS where it resides. Different from the stub area, the NSSA allows AS external routes to be imported and forwarded in the entire AS.

Configuring OSPF Stub Areas

Configuring OSPF NSSA Areas

Adjusting OSPF Route Selection

To use OSPF more flexibly on the existing network and meet various user requirements, you can configure different parameters to control OSPF routing.

Adjusting OSPF Route Selection

Controlling OSPF Routing Information

In practical applications, to meet network requirements, you can configure different parameters to accurately control the advertising and receiving of OSPF routes.

Controlling OSPF Routing Information

Controlling the convergence speed of OSPF routes

To enable OSPF to quickly detect changes in the network topology, you can speed up OSPF route convergence. To decrease the impact of route flapping on the network and relieve loads on devices, you can lower the convergence speed of OSPF routes.

Configuring OSPF Fast Convergence

Improving the Reliability of an OSPF Network

  • OSPF IP FRR pre-computes a backup link by using the Loop-Free Alternate (LFA) algorithm, and then adds the backup link and the primary link to the forwarding table. In the case of failures, OSPF IP FRR can fast switch traffic to the backup link before routes on the control plane converge. This prevents traffic interruption and thus protects traffic and improves reliability of an OSPF network.

  • By default, on broadcast networks, the interval for OSPF to send Hello packets is 10 seconds; on NBMA networks, the interval for sending Hello packets is 30 seconds. The interval for declaring a neighbor Down, that is, the dead time after which the neighbor relationship becomes invalid, is four times the interval for sending Hello packets. If the switch modules does not receive a Hello packet from its neighbor within the dead time, the switch modules deletes the neighbor. That is, the switch modules detects the neighbor faults in seconds. This causes a large number of packets to be lost on a high-speed network.

    Bidirectional Forwarding Detection (BFD) is introduced to solve the preceding problem in the existing detection mechanism. BFD ensures the detection interval in milliseconds. Instead of replacing the Hello mechanism of OSPF, BFD works with OSPF to fast detect the adjacency fault. In addition, BFD instructs OSPF to recalculate corresponding routes for correct packet forwarding.

  • When a switch modules restarts or performs the active/standby switchover, it directly ages all routing entries in the Forward Information Base (FIB) table. This results in route interruption. In addition, neighboring switch moduless remove this switch modules from the neighbor list, and notify other switch moduless. This causes the re-calculation of SPF. If this switch modules recovers within a few seconds, the neighbor relationship becomes unstable. This results in route flapping.

    After being enabled with OSPF Graceful Restart (GR), a switch modules can ensure continuous packet forwarding if it restarts just for abnormities. In such a case, route flapping is avoided during the short restart of the switch modules.

Configuring OSPF IP FRR

Configuring BFD for OSPF

Configuring OSPF GR Helper

Improving the Stability of an OSPF Network

In practical applications, you can improve the stability of the OSPF network to reduce route flapping on the OSPF network and enable the device to work in a normal state for a long time.

Improving the Stability of an OSPF Network

Improving the Security of an OSPF Network

In a network demanding high security, you can configure OSPF authentication and adopt the GTSM mechanism to improve the security of the OSPF network.

Improving the Security of an OSPF Network

Updated: 2019-08-09

Document ID: EDOC1000041694

Views: 59254

Downloads: 3623

Average rating:
This Document Applies to these Products
Related Version
Related Documents
Previous Next