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静态BFD与静态路由联动的配置案例

2019-07-18 发表

组网及说明


SR88X-UP上存在两条到达loop0 5.5.5.5的静态路由,下一跳分别为g3/3/2和g3/1/9,这两条静态路由形成备份,下一跳为g3/3/2的静态路由优先级高,作为主路由。该路由可达时,下一跳为g3/1/9的静态路作为备份路由。

在SR88X-UP上通过静态路由、Track与静态BFD联动,实时判断主路由是否可达。当主路由不可达时,BFD能够快速地检测到路由故障,使得备份路由生效。



配置步骤

配置:

[SR88X-down]track 1 bfd static abc

bfd static abc peer-ip 2.2.2.2 interface GigabitEthernet3/3/2 source-ip 2.2.2.1 discriminator local 4321 remote 1234

 bfd min-transmit-interval 10

 bfd min-receive-interval 10

 bfd detect-multiplier 3



[SR88X-up] track 1 bfd static abc

[SR88X-up] bfd static abc peer-ip 2.2.2.1 interface GigabitEthernet4/1/4 source-ip 2.2.2.2 discriminator local 1234 remote 4321

 bfd min-transmit-interval 10

 bfd min-receive-interval 10

 bfd detect-multiplier 3


[SR88X-up]display track all

Track ID: 1

  State: Positive

  Duration: 0 days 0 hours 5 minutes 56 seconds

  Tracked object type: BFD static

  Notification delay: Positive 0, Negative 0 (in seconds)

  Tracked object:

    BFD static session name: abc


[SR88X-up]display ip routing-table 5.5.5.5

Summary count : 1

Destination/Mask   Proto   Pre Cost        NextHop         Interface

5.5.5.5/32         Static  60  0           2.2.2.1         GE4/1/4


验证过程:

[SR88X-up-GigabitEthernet4/1/4]shut

[SR88X-up-GigabitEthernet4/1/4]%Jul 18 07:38:05:574 2019 SR88X-up BFD/5/BFD_CHANGE_FSM: -MDC=1; Sess[2.2.2.2/2.2.2.1, LD/RD:1234/4321, Interface:GE4/1/4, SessType:Ctrl, LinkType:INET], Ver:1, Sta: UP->DOWN, Diag: 1 (Control Detection Time Expired)


[SR88X-up]display track all

Track ID: 1

  State: Negative

  Duration: 0 days 0 hours 0 minutes 18 seconds

  Tracked object type: BFD static

  Notification delay: Positive 0, Negative 0 (in seconds)

  Tracked object:

    BFD static session name: abc

 

[SR88X-up]display ip routing-table 5.5.5.5

Summary count : 1

Destination/Mask   Proto   Pre Cost        NextHop         Interface

5.5.5.5/32         Static  80  0           1.1.1.2         GE4/1/1


[SR88X-up]ping 5.5.5.5

Ping 5.5.5.5 (5.5.5.5): 56 data bytes, press CTRL_C to break

56 bytes from 5.5.5.5: icmp_seq=0 ttl=254 time=9.498 ms

56 bytes from 5.5.5.5: icmp_seq=1 ttl=254 time=2.469 ms

56 bytes from 5.5.5.5: icmp_seq=2 ttl=254 time=2.172 ms

56 bytes from 5.5.5.5: icmp_seq=3 ttl=254 time=2.086 ms

56 bytes from 5.5.5.5: icmp_seq=4 ttl=254 time=2.180 ms


[SR88X-up]int g 4/1/4

[SR88X-up-GigabitEthernet4/1/4]undo shut


%Jul 18 07:44:41:600 2019 SR88X-up BFD/5/BFD_CHANGE_FSM: -MDC=1; Sess[2.2.2.2/2.2.2.1, LD/RD:1234/4321, Interface:GE4/1/4, SessType:Ctrl, LinkType:INET], Ver:1, Sta: DOWN->UP, Diag: 0 (No Diagnostic)


 [SR88X-up]display ip routing-table 5.5.5.5

Destination/Mask   Proto   Pre Cost        NextHop         Interface

5.5.5.5/32         Static  60  0           2.2.2.1         GE4/1/4


 [SR88X-up]display track all

Track ID: 1

  State: Positive

  Duration: 0 days 0 hours 0 minutes 25 seconds

  Tracked object type: BFD static

  Notification delay: Positive 0, Negative 0 (in seconds)

  Tracked object:

    BFD static session name: abc


 [SR88X-up]ping 5.5.5.5

Ping 5.5.5.5 (5.5.5.5): 56 data bytes, press CTRL_C to break

56 bytes from 5.5.5.5: icmp_seq=0 ttl=255 time=1.012 ms

56 bytes from 5.5.5.5: icmp_seq=1 ttl=255 time=0.646 ms

56 bytes from 5.5.5.5: icmp_seq=2 ttl=255 time=0.621 ms

56 bytes from 5.5.5.5: icmp_seq=3 ttl=255 time=1.021 ms

56 bytes from 5.5.5.5: icmp_seq=4 ttl=255 time=0.656 ms



 

配置关键点

配置限制和指导:

1.如果对端创建了静态BFD会话,那么本端必须创建静态BFD会话。

2.首次创建静态BFD会话时,必须指定静态BFD会话的对端IPv4或IPv6地址。系统仅检查IP地址的形式,不检查其正确性。指定错误的对端IP地址或源IP地址均会导致静态BFD会话无法建立。

3.不同的静态BFD会话的本地标识符不能相同。