Example for Configuring Multi-Hop BFD for IPv6

Networking Requirements

In Figure 1, SwitchA is connected to SwitchC through SwitchB. SwitchA and SwitchC communicate with each other using static routes. The customer requires that link failures between switches be quickly detected.

Figure 1 Networking diagram of configuring multi-hop BFD for IPv6

Configuration Roadmap

The configuration roadmap is as follows:

Configure a BFD6 session on SwitchA to detect the multi-hop link from SwitchA to SwitchC.
Configure a BFD6 session on SwitchC to detect the multi-hop link from SwitchC to SwitchA.

The intervals for sending and receiving BFD packets and local detection multiplier retain the default settings.

Procedure

Assign IPv6 addresses to the interfaces on SwitchA, SwitchB, and SwitchC.

# Assign an IPv6 address to the interface on SwitchA.

<HUAWEI> system-view
[HUAWEI] sysname SwitchA
[SwitchA] ipv6
[SwitchA] interface GigabitEthernet 0/0/1
[SwitchA-GigabitEthernet0/0/1] undo portswitch
[SwitchA-GigabitEthernet0/0/1] ipv6 enable
[SwitchA-GigabitEthernet0/0/1] ipv6 address fc00:0:0:2001::1 64
[SwitchA-GigabitEthernet0/0/1] quit

# Assign an IPv6 address to the interface on SwitchB.

<HUAWEI> system-view
[HUAWEI] sysname SwitchB
[SwitchB] ipv6
[SwitchB] interface GigabitEthernet 0/0/1
[SwitchB-GigabitEthernet0/0/1] undo portswitch
[SwitchB-GigabitEthernet0/0/1] ipv6 enable
[SwitchB-GigabitEthernet0/0/1] ipv6 address fc00:0:0:2001::2 64
[SwitchB-GigabitEthernet0/0/1] quit
[SwitchB] interface GigabitEthernet 0/0/2
[SwitchB-GigabitEthernet0/0/2] undo portswitch
[SwitchB-GigabitEthernet0/0/2] ipv6 enable
[SwitchB-GigabitEthernet0/0/2] ipv6 address fc00:0:0:2002::1 64
[SwitchB-GigabitEthernet0/0/2] quit

# Assign an IPv6 address to the interface on SwitchC.

<HUAWEI> system-view
[HUAWEI] sysname SwitchC
[SwitchC] ipv6
[SwitchC] interface GigabitEthernet 0/0/2
[SwitchC-GigabitEthernet0/0/2] undo portswitch
[SwitchC-GigabitEthernet0/0/2] ipv6 enable
[SwitchC-GigabitEthernet0/0/2] ipv6 address fc00:0:0:2002::2 64
[SwitchC-GigabitEthernet0/0/2] quit

Configure IPv6 static routes between SwitchA and SwitchC.
# Configure the static route on SwitchA.
```
[SwitchA] ipv6 route-static fc00:0:0:2002:: 64 fc00:0:0:2001::2
```
# Configure the static route on SwitchC.
```
[SwitchC] ipv6 route-static fc00:0:0:2001:: 64 fc00:0:0:2002::1
```

Configure multi-hop BFD between SwitchA and SwitchC.

# Configure a BFD6 session on SwitchA to SwitchC. You do not need to bind the BFD6 session to an outbound interface.

[SwitchA] bfd
[SwitchA-bfd] quit
[SwitchA] bfd atoc bind peer-ipv6 fc00:0:0:2002::2
[SwitchA-bfd-session-atoc] discriminator local 10
[SwitchA-bfd-session-atoc] discriminator remote 20
[SwitchA-bfd-session-atoc] commit
[SwitchA-bfd-session-atoc] quit

# Configure a BFD6 session on SwitchC to SwitchA. You do not need to bind the BFD6 session to an outbound interface.

[SwitchC] bfd
[SwitchC-bfd] quit
[SwitchC] bfd ctoa bind peer-ipv6 fc00:0:0:2001::1
[SwitchC-bfd-session-ctoa] discriminator local 20
[SwitchC-bfd-session-ctoa] discriminator remote 10
[SwitchC-bfd-session-ctoa] commit
[SwitchC-bfd-session-ctoa] quit

Verify the configuration.

# When the network runs stably, run the display bfd session all verbose command on SwitchA and SwitchC. A multi-hop BFD6 session exists and its status is Up.

The command output on SwitchA is used as an example.

[SwitchA] display bfd session all verbose
--------------------------------------------------------------------------------
Session MIndex : 256       (Multi Hop) State : Up        Name : atoc
--------------------------------------------------------------------------------
Local Discriminator    : 10               Remote Discriminator   : 20
Session Detect Mode    : Asynchronous Mode Without Echo Function
BFD Bind Type          : Peer IP Address
Bind Session Type      : Static
Bind Peer IP Address   : FC00:0:0:2002::2
Bind Interface         : -
FSM Board Id           : 0                TOS-EXP                : 7
Min Tx Interval (ms)   : 1000             Min Rx Interval (ms)   : 1000
Actual Tx Interval (ms): 1000             Actual Rx Interval (ms): 1000
Local Detect Multi     : 3                Detect Interval (ms)   : 3000
Echo Passive           : Disable          Acl Number             : -
Destination Port       : 4784             TTL                    : 255
Proc Interface Status  : Disable          Process PST            : Disable
WTR Interval (ms)      : -
Active Multi           : 3                DSCP                   : -
Last Local Diagnostic  : No Diagnostic
Bind Application       : No Application Bind
Session TX TmrID       : -                Session Detect TmrID   : -
Session Init TmrID     : -                Session WTR TmrID      : -
Session Echo Tx TmrID  : -
PDT Index              : FSM-0 | RCV-0 | IF-0 | TOKEN-0
Session Description    : -
--------------------------------------------------------------------------------

Total UP/DOWN Session Number : 1/0

Configuration Files

SwitchA configuration file

#
sysname SwitchA
#
ipv6
#
bfd
#
interface GigabitEthernet0/0/1
 undo portswitch
 ipv6 enable
 ipv6 address FC00:0:0:2001::1/64
#
bfd atoc bind peer-ipv6 FC00:0:0:2002::2
 discriminator local 10
 discriminator remote 20
 commit
#
ipv6 route-static FC00:0:0:2002:: 64 FC00:0:0:2001::2 
#
return

SwitchB configuration file

#
sysname SwitchB
#
ipv6
#
interface GigabitEthernet0/0/1
 undo portswitch
 ipv6 enable
 ipv6 address FC00:0:0:2001::2/64
#
interface GigabitEthernet0/0/2
 undo portswitch
 ipv6 enable
 ipv6 address FC00:0:0:2002::1/64
#
return

SwitchC configuration file

#
sysname SwitchC
#
ipv6
#
bfd
#
interface GigabitEthernet0/0/2
 undo portswitch
 ipv6 enable
 ipv6 address FC00:0:0:2002::2/64
#
bfd ctoa bind peer-ipv6 FC00:0:0:2001::1
 discriminator local 20
 discriminator remote 10
 commit
#
ipv6 route-static FC00:0:0:2001:: 64 FC00:0:0:2002::1 
#
return