H3C 5554C-EI-D配置完bfd后状态异常

机器型号：H3C 5554C-EI-D

问题描述：

1.配置完bfd以后，state都是down状态

2.路由都是选的备用路由

3.断掉172.21.64.153这个地址，路由就不通了

[dr-scp-sw1]display bfd session Total Session 

Num: 6 Up Session Num: 0 Init Mode: Active 

 IPv4 Session Working Under Echo Mode: 

 LD SourceAddr DestAddr State Holdtime Interface 

 97 172.21.64.148 172.21.64.145 Down / Vlan2163  

[dr-scp-sw1]display ip routing-table protocol static 

 Summary Count : 57 Static Routing table Status : <Active> 

Summary Count : 57 

 Destination/Mask Proto Pre Cost NextHop Interface 

172.21.51.1/32 Static 65 0 172.21.64.153 Vlan2164

 配置信息：

bfd echo-source-ip 10.10.10.10

ip route-static 172.21.51.1 32 vlan-interface 2163 172.21.64.145 bfd echo-packet

ip route-static 172.21.51.1 32 vlan-interface 2164 172.21.64.153 preference 65

interface Vlan-interface 2163 

bfd min-echo-receive-interval 100 

bfd detect-multiplier 3

PC需要通过两个交换机去访问172.21.51.1这个地址

主用路由走172.21.64.145这个地址，当172.21.64.145地址down掉后，走72.21.64.153

当72.21.64.145恢复以后，继续走72.21.64.145