起因，家里的网络最近莫名其妙的开始阻断，恢复时间不等，故做了简单的网络备份，此篇文章进行相关记录

1.网络结构

backup 1 node(10.2.0.1)——————–|
(10.1.0.3)                                                |
|                                                              |
| (proxy ip 10.0.0.1/32)                     (10.2.0.2)
proxy main node(10.1.0.1)—-(10.1.0.2)home
|                                                         (10.3.0.2)
|                                                               |
(10.1.0.4)                                                 |
backup 2 node (10.3.0.1)——————–|

2.简单运行逻辑

所有备份的节点需要和proxy main node和home连接（笔者使用wireguard连接），同时建立bgp时，启用rr（路由反射），启用bfd

proxy main node宣告路由10.0.0.1/32，启用bfd

home设置backup node路由权重（此处使用weight属性），启用bfd

设置完成后，当proxy main node与home的链路出现问题，将会毫秒级切换至其他backup node至proxy main node。

3.配置过程

proxy main node:

bfd
profile bgpcheck
detect-multiplier 2
exit
!
exit
router bgp 59598
 neighbor 10.1.0.2 remote-as 59598
 neighbor 10.1.0.2 bfd profile bgpcheck
 neighbor 10.1.0.3 remote-as 59598
 neighbor 10.1.0.4 remote-as 59598

backup 1 node:

bfd
 profile bgpcheck
  detect-multiplier 2
 exit
 !
exit
router bgp 59598
 neighbor 10.1.0.1 remote-as 59598
 neighbor 10.2.0.2 remote-as 59598
 neighbor 10.2.0.2 bfd profile bgpcheck
 address-family ipv4 unicast
  neighbor 10.2.0.2 route-reflector-client
 exit-address-family
exit

backup 2 node:

bfd
 profile bgpcheck
  detect-multiplier 2
 exit
 !
exit
router bgp 59598
 neighbor 10.1.0.1 remote-as 59598
 neighbor 10.3.0.2 remote-as 59598
 neighbor 10.3.0.2 bfd profile bgpcheck
 address-family ipv4 unicast
  neighbor 10.3.0.2 route-reflector-client
 exit-address-family
exit

home:

bfd
 profile bgpcheck
  detect-multiplier 2
 exit
 !
exit
route-map main-node-in permit 10
 set ip next-hop peer-address
 set weight 1000
exit
route-map backup-1-node-in permit 10
 set ip next-hop peer-address
 set weight 999
exit
route-map backup-2-node-in permit 10
 set ip next-hop peer-address
 set weight 998
exit
router bgp 59598
 neighbor 10.1.0.1 remote-as 59598
 neighbor 10.1.0.1 bfd profile bgpcheck
 neighbor 10.2.0.1 remote-as 59598
 neighbor 10.2.0.1 bfd profile bgpcheck
 neighbor 10.3.0.1 remote-as 59598
 neighbor 10.3.0.1 bfd profile bgpcheck
 address-family ipv4 unicast
  neighbor 10.1.0.1 route-map main-node-in in
  neighbor 10.2.0.1 route-map backup-1-node-in in
  neighbor 10.3.0.1 route-map backup-2-node-in in
 exit-address-family
exit