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The multicast IP address of BFD is set.
To implement single-hop BFD on a Layer 2 forwarding link, BFD needs to use a multicast IP
address. By default, BFD uses the multicast IP address 224.0.0.184.
NOTE
l
If this multicast IP address is used by other protocols on the network, you must change the multicast
IP address. The S3700s at both ends of the BFD session must use the same multicast IP address.
l
If multiple BFD sessions exist on a path, for example, Layer 3 interfaces are connected through Layer
2 switching devices that support BFD, you must configure different default multicast IP addresses for
the devices where different BFD sessions are established. In this manner, BFD packets can be correctly
forwarded.
----End
6.3.4 Creating a BFD Session
Context
Do as follows on S3700s at both ends of the link to be detected.
Procedure
Step 1
Run:
system-view
The system view is displayed.
Step 2
Run the following command as required.
l
If the VLANIF interface has an IP address, run:
bfd
cfg-name
bind
peer-ip
peer-ip
[
vpn-instance
vpn-instance-name
] [
interface
interface-
type
interface-number
] [
source-ip
source-ip
]
–
When creating a single-hop BFD session for the first time, you must bind the single-hop
BFD session to the peer IP address and the local address. In addition, the configuration
of the single-hop BFD session cannot be changed after being created.
–
When BFD configuration items are created, the system checks only the format of the IP
address rather than the correctness. A BFD session cannot be established if an incorrect
peer IP address or source IP address is bound.
–
When BFD and URPF are used together, URPF checks the source IP address of the
received BFD packets. In this case, you need to specify the correct source IP address of
BFD packets by setting the
source-ip
parameter when binding a BFD session to prevent
BFD packets from being discarded incorrectly.
l
For a Layer 2 interface, run:
bfd
cfg-name
bind
peer-ip
default-ip
interface
interface-type
interface-number
[
source-
ip
source-ip
]
Step 3
Set the discriminators.
l
Run:
discriminator
local
discr-value
The local discriminator is set.
l
Run:
discriminator
remote
discr-value
Quidway S3700 Series Ethernet Switches
Configuration Guide - Reliability
6 BFD Configuration
Issue 01 (2011-10-26)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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