Example for Associating a BFD Session with an Interface
This section provides an example for associating a BFD session with an interface to trigger rapid route convergence if a fault occurs.
Networking Requirements
On the network shown in Figure 1, transmission devices exist on the link between Device A and Device B. A BFD session is associated with an interface on the Devices. If the link between GE 0/1/0 on Device A and GE 0/1/0 on Device B fails, associate a BFD session with an interface to detect the fault. The BFD session status change affects the interface protocol status change, triggering rapid route convergence.
Configuration Roadmap
The configuration roadmap is as follows:
Configure a BFD session on Device A.
Configure a BFD session on Device B.
Associate the BFD session and an interface on Device A.
Associate the BFD session and an interface on Device B.
Data Preparation
To complete the configuration, you need the following data:
Peer IP address monitored by BFD
IP address of a local interface that sends and receives BFD control packets
Local and remote discriminators of BFD sessions
Procedure
- Assign IP addresses to the interfaces connecting Device A and Device B.
# Assign an IP address to the interface on Device A.
<HUAWEI> system-view [~HUAWEI] sysname DeviceA [*HUAWEI] commit [~DeviceA] interface gigabitethernet 0/1/0 [~DeviceA-GigabitEthernet0/1/0] undo shutdown [*DeviceA-GigabitEthernet0/1/0] ip address 10.1.1.1 24 [*DeviceA-GigabitEthernet0/1/0] commit [~DeviceA-GigabitEthernet0/1/0] quit
# Assign an IP address to the interface on Device B.
<HUAWEI> system-view [~HUAWEI] sysname DeviceB [*HUAWEI] commit [~DeviceB] interface gigabitethernet 0/1/0 [~DeviceB-GigabitEthernet0/1/0] undo shutdown [*DeviceB-GigabitEthernet0/1/0] ip address 10.1.1.2 24 [*DeviceB-GigabitEthernet0/1/0] commit [~DeviceB-GigabitEthernet0/1/0] quit
After the configuration is complete, Device A and Device B can ping each other. The following example uses the command output on Device A.
[~DeviceA] ping 10.1.1.2 PING 10.1.1.2 : 56 data bytes, press CTRL_C to break Reply from 10.1.1.2: bytes=56 Sequence=1 ttl=255 time=3 ms Reply from 10.1.1.2: bytes=56 Sequence=2 ttl=255 time=1 ms Reply from 10.1.1.2: bytes=56 Sequence=3 ttl=255 time=1 ms Reply from 10.1.1.2: bytes=56 Sequence=4 ttl=255 time=1 ms Reply from 10.1.1.2: bytes=56 Sequence=5 ttl=255 time=1 ms --- 10.1.1.2 ping statistics --- 5 packet(s) transmitted 5 packet(s) received 0.00% packet loss round-trip min/avg/max = 1/1/3 ms
- Configure single-hop BFD.
# Enable BFD on Device A, and configure a BFD session with Device B.
[~DeviceA] bfd [*DeviceA-bfd] quit [*DeviceA] bfd pis bind peer-ip default-ip interface gigabitethernet 0/1/0 [*DeviceA-bfd-session-pis] discriminator local 1 [*DeviceA-bfd-session-pis] discriminator remote 2 [*DeviceA-bfd-session-pis] commit [~DeviceA-bfd-session-pis] quit
# Enable BFD on Device B, and configure a BFD session with Device A.
[~DeviceB] bfd [*DeviceB-bfd] quit [*DeviceB] bfd pis bind peer-ip default-ip interface gigabitethernet 0/1/0 [*DeviceB-bfd-session-pis] discriminator local 2 [*DeviceB-bfd-session-pis] discriminator remote 1 [*DeviceB-bfd-session-pis] commit [~DeviceB-bfd-session-pis] quit
After completing the preceding configurations, run the display bfd session all verbose command on Device A or Device B. The command output shows that a single-hop BFD session has been established and its status is Up. The following example uses the command output Device A.
[~DeviceA] display bfd session all verbose (w): State in WTR (*): State is invalid ------------------------------------------------------------------------------ (One Hop) State : Up Name : pis ------------------------------------------------------------------------------ Local Discriminator : 1 Remote Discriminator : 2 Session Detect Mode : Asynchronous Mode Without Echo Function BFD Bind Type : Interface(GigabitEthernet0/1/0) Bind Session Type : Static Bind Peer IP Address : 224.0.0.184 Bind Interface : GigabitEthernet0/1/0 FSM Board Id : 1 TOS-EXP : 7 Min Tx Interval (ms) : 10 Min Rx Interval (ms) : 10 Actual Tx Interval (ms): 10 Actual Rx Interval (ms): 10 Local Detect Multi : 3 Detect Interval (ms) : 30 Echo Passive : Disable Acl Number : - Destination Port : 3784 TTL : 255 Proc Interface Status : Disable Process PST : Disable WTR Interval (ms) : 0 Config PST : Disable Active Multi : 3 Last Local Diagnostic : No Diagnostic Bind Application : No Application Bind Session TX TmrID : 0 Session Detect TmrID : 0 Session Init TmrID : - Session WTR TmrID : - Session Echo Tx TmrID : - Session Description : - ------------------------------------------------------------------------------ Total UP/DOWN Session Number : 1/0
- Associate the BFD sessions with the interfaces.
# Configure Device A.
[~DeviceA] bfd pis [*DeviceA-bfd-session-pis] process-interface-status [*DeviceA-bfd-session-pis] commit [~DeviceA-bfd-session-pis] quit
# Configure Device B.
[~DeviceB] bfd pis [*DeviceB-bfd-session-pis] process-interface-status [*DeviceB-bfd-session-pis] commit [~DeviceB-bfd-session-pis] quit
- Verify the configuration.
After completing the configuration, run the display bfd session all verbose command on Device A or Device B. The command output shows that Proc Interface Status is Enable. The following example uses the command output on Device A.
[~DeviceA] display bfd session all verbose (w): State in WTR (*): State is invalid ------------------------------------------------------------------------------ (One Hop) State : Up Name : pis ------------------------------------------------------------------------------ Local Discriminator : 1 Remote Discriminator : 2 Session Detect Mode : Asynchronous Mode Without Echo Function BFD Bind Type : Interface(GigabitEthernet0/1/0) Bind Session Type : Static Bind Peer IP Address : 224.0.0.184 Bind Interface : GigabitEthernet0/1/0 FSM Board Id : 1 TOS-EXP : 7 Min Tx Interval (ms) : 10 Min Rx Interval (ms) : 10 Actual Tx Interval (ms): 10 Actual Rx Interval (ms): 10 Local Detect Multi : 3 Detect Interval (ms) : 30 Echo Passive : Disable Acl Number : - Destination Port : 3784 TTL : 255 Proc Interface Status : Enable Process PST : Disable WTR Interval (ms) : 0 Config PST : Disable Active Multi : 3 Last Local Diagnostic : No Diagnostic Bind Application : No Application Bind Session TX TmrID : 0 Session Detect TmrID : 0 Session Init TmrID : - Session WTR TmrID : - Session Echo Tx TmrID : - Session Description : - ------------------------------------------------------------------------------ Total UP/DOWN Session Number : 1/0
Run the shutdown command on GE 0/1/0 of Device B.
[~DeviceB] interface gigabitethernet 0/1/0 [~DeviceB-GigabitEthernet0/1/0] shutdown [*DeviceB-GigabitEthernet0/1/0] commit [~DeviceB-GigabitEthernet0/1/0] quit
Run the display bfd session all verbose and display interface commands on Device A. The command output shows that the BFD session is Down and GE 0/1/0 is Up.
[~DeviceA] display bfd session all verbose (w): State in WTR (*): State is invalid ------------------------------------------------------------------------------ (One Hop) State : Down Name : pis ------------------------------------------------------------------------------ Local Discriminator : 1 Remote Discriminator : 2 Session Detect Mode : Asynchronous Mode Without Echo Function BFD Bind Type : Interface(GigabitEthernet0/1/0) Bind Session Type : Static Bind Peer IP Address : 224.0.0.184 Bind Interface : GigabitEthernet0/1/0 FSM Board Id : 1 TOS-EXP : 7 Min Tx Interval (ms) : 10 Min Rx Interval (ms) : 10 Actual Tx Interval (ms): 2100 Actual Rx Interval (ms): 2100 Local Detect Multi : 3 Detect Interval (ms) : 0 Echo Passive : Disable Acl Number : - Destination Port : 3784 TTL : 255 Proc Interface Status : Enable Process PST : Disable WTR Interval (ms) : 0 Config PST : Disable Active Multi : 3 Last Local Diagnostic : Control Detection Time Expired Bind Application : No Application Bind Session TX TmrID : 2725402068 Session Detect TmrID : - Session Init TmrID : - Session WTR TmrID : - Session Echo Tx TmrID : - Session Description : - ------------------------------------------------------------------------------ Total UP/DOWN Session Number : 0/1 [~DeviceA] display interface gigabitethernet 0/1/0 GigabitEthernet0/1/0 current state : UP (ifindex: 20) Line protocol current state : DOWN (BFD status down) Description: HUAWEI, GigabitEthernet0/1/0 Interface Route Port,The Maximum Transmit Unit is 1500 Internet Address is 10.1.1.2/24 IP Sending Frames' Format is PKTFMT_ETHNT_2, Hardware address is 00e0-fc12-7890 Current BW: 100 Mbits Last physical up time : 2010-07-31 09:35:03 Last physical down time : 2010-08-03 02:58:22 Current system time: 2010-08-03 03:02:48 Statistics last cleared:never Last 300 seconds input rate 0 bits/sec, 4 packets/sec Last 300 seconds output rate 0 bits/sec, 4 packets/sec Input: 0 bytes, 662126 packets Output: 0 bytes, 661789 packets Input: Unicast: 662111 packets, Multicast: 12 packets Broadcast: 3 packets, JumboOctets: 0 packets CRC: 0 packets, Symbol: 0 packets Overrun: 0 packets, InRangeLength: 0 packets LongPacket: 0 packets, Jabber: 0 packets, Alignment: 0 packets Fragment: 0 packets, Undersized Frame: 0 packets RxPause: 0 packets Output: Unicast: 661784 packets, Multicast: 3 packets Broadcast: 2 packets, JumboOctets: 0 packets Lost: 0 packets, Overflow: 0 packets, Underrun: 0 packets System: 0 packets, Overruns: 0 packets TxPause: 0 packets Last 300 seconds input utility rate: 0.00% Last 300 seconds output utility rate: 0.00%
Configuration Files
Device A configuration file
# sysname DeviceA # bfd # interface GigabitEthernet0/1/0 undo shutdown ip address 10.1.1.1 255.255.255.0 # bfd pis bind peer-ip default-ip interface GigabitEthernet0/1/0 discriminator local 1 discriminator remote 2 process-interface-status return
Device B configuration file
# sysname DeviceB # bfd # interface GigabitEthernet0/1/0 undo shutdown ip address 10.1.1.2 255.255.255.0 # bfd pis bind peer-ip default-ip interface GigabitEthernet0/1/0 discriminator local 2 discriminator remote 1 process-interface-status return