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.


Configuration Guide - Reliability

CloudEngine 12800 and 12800E V200R002C50

This document describes the configurations of Reliability, including BFD Configuration, VRRP Configuration, DLDP Configuration, Smart Link and Monitor Link Configuration, EFM Configuration, and CFM Configuration.
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).
Licensing Requirements and Limitations for BFD

Licensing Requirements and Limitations for BFD

Involved Network Elements

Other network elements are required to support BFD functions.

Licensing Requirements

BFD is a basic feature of a switch and is not under license control.

BFD for IPv6 can be used only on a device enabled with IPv6. IPv6 requires a license. By default, IPv6 of a newly purchased device is disabled. To use IPv6, apply for and purchase the license from the equipment supplier.

Version Requirements

Table 2-6 Products and minimum version supporting BFD


Minimum Version Required

CE12804, CE12808, CE12812




CE12804S, CE12808S




Feature Limitations

When BFD is used with other features, the following limitations apply:

  • A BFD session cannot be configured on a Generic Routing Encapsulation (GRE) tunnel or an IPv6 tunnel.

  • The single-hop BFD session bound to an Eth-Trunk incorrectly reports a Down event when the Eth-Trunk member interface goes Down or the card where the Eth-Trunk is configured is not properly installed.

  • If BFD and unicast reverse path forwarding (URPF) are used together, to prevent BFD packets from being discarded, the source IP address must be configured correctly before a BFD session is bound to the IP address. URPF checks the format of the source IP addresses in received packets and discards the packets whose source IP addresses are incorrect.

  • When using BFD for Perlink, ensure that URPF is disabled on the transmit end of BFD echo packets. Otherwise, the BFD echo function may become invalid.

  • In V200R003C00 and later versions, BFD packets sampled by NetStream or sFlow cannot be output on devices that support hardware-based BFD.

The following limitations apply to BFD sessions:

  • The created BFD session for IP cannot be modified, and must be bound to the remote IP address and local interface.

  • When a BFD session for IP is created, the system checks only the validity of the IP address format.

  • When using automatically negotiated discriminators to configure a static BFD session, you must configure the source address and specify the remote unicast IPv4 address. Multicast IPv4 address cannot be used.

  • In V100R005C00 and later versions, the source IP address of the BFD session for Link-bundle must be the IP address of the local Layer 3 Eth-Trunk.

  • The device supports BFD timeout detection to prevent the BFD session Down event from being reported incorrectly. After a BFD session is set up, the device starts BFD timeout detection when receiving Up packets from the remote end. Otherwise, the device reports the BFD session Down event only when the first packet expires.

    The timeout interval of the first packet is 50s.

  • When the BFD session is negotiated successfully, if the device receives BFD session Down packets and the remote discriminator in packets is the same as the local discriminator of the device, the BFD session Down event will be reported incorrectly.

  • The CE12800 and CE12800E support hardware-based BFD. For the CE12800, only the CE-L48XS-FG, CE-L48XS-FD1, CE-L24LQ-FD, CE-L36LQ-FD, CE-L12CQ-FD, CE-L36CQ-FG, CE-L36CQ-FD1, CE-L36CQ-SD, CE-L16CQ-FD, CE-L08CF-FG1, and CE-L36CQ-FD support hardware-based BFD.
  • In V200R002C50 and earlier versions, the device does not support VBDIF interface bound to the BFD session.

BFD session parameters have the following limitations:

  • The local discriminator of the local system must be the same as the remote discriminator of the remote system. Additionally, the remote discriminator of the local system must be the same as the local discriminator of the remote system. Otherwise, static BFD sessions cannot be established.

  • In V200R002C50 and earlier versions, the local discriminator and the remote discriminator of the BFD session bound to the default multicast address must be different.

  • Both the minimum interval for sending BFD packets and the local detection multiplier determine the detection time of a BFD session. It is recommended that 300 ms*5, 500 ms*4, or 1000 ms*3 be used.

  • It is recommended that the BFD detection interval be greater than the fault convergence time of Eth-Trunk member interfaces or the time taken to rectify the intermittent disconnection fault of physical interfaces.

  • In V200R002C50 and later versions, you are advised to run the port-status fast-detect enable command to enable the chip to rapidly detect the physical status change of a physical interface when connecting the BFD-enabled switch to a transmission device. In addition, the BFD detection interval of 500 ms*4, 1000 ms*3, or a larger value should be used.

  • If the wait to restore (WTR) time is set, set the same WTR time at both ends. Otherwise, when the BFD session status changes at one end, applications at both ends will detect different BFD session statuses.

  • The port state table (PST) is invalid for logical interfaces such as the Eth-Trunk and VLANIF interfaces.

  • If the BFD session on a trunk or VLANIF member interface allows BFD to modify the PST, and the interface is configured with the BFD session, you must configure the WTR time for the BFD session for detecting the interface. This prevents the BFD session on the interface from flapping when the member interface joins or leaves the interface.

  • When the CPCAR value is used, BFD sessions supported by each card include the BFD sessions established on the card and the BFD sessions that are established on other cards and traverse this card. If packets of BFD sessions traverse the fully configured card, run the car command in the attack defense policy view to increase the CPCAR value of BFD packets.

Features associated with BFD:

BFD can be used with static route, RIP, OSPF, IS-IS, BGP, VRRP, PIM, LDP-LSP, RSVP, CR-LSP, VXLAN, SR-TE, and M-LAG.

Updated: 2019-03-21

Document ID: EDOC1000166606

Views: 125296

Downloads: 90

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