Prerequisites for BFD Debug Enhancement
Bidirectional Forwarding Detection (BFD) feature must be running on the device.
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The Bidirectional Forwarding Detection (BFD) Debug Enhancement feature enables logging of debugging information for critical BFD events, normal BFD events, and BFD packets. This feature enables BFD event traces and BFD event logs. This feature allows network engineers and operaters to easily identify and analyze issues with BFD sessions.
Bidirectional Forwarding Detection (BFD) feature must be running on the device.
The Bidirectional Forwarding Detection (BFD) event trace logs cannot store more than 65536 elements in a BFD instance. Once the log elements reach this limit, new log entries replace the old log entries.
The Bidirectional Forwarding Detection (BFD) Debug Enhancement feature enables logging of debugging information for critical BFD events, normal BFD events, and BFD packets. This feature enables BFD event traces and BFD event logs.
The Event Tracer subsystem in the BFD Debug Enhancement feature helps network engineers trace BFD events. This subsystem generates debugging information that can be extracted and analyzed. You can optionally store the traced data in a file for further analysis.
The Event Log Architecture in the BFD Debug Enhancement feature is classified into three types:
BFD Critical—Logs debugging information about all critical BFD event traces, whenever the BFD session attains the DOWN state.
BFD Event—Logs debugging information about all BFD events that can be logged using the debug bfd event command.
BFD Packet—Logs debugging information about all BFD packets that can be logged using the debug bfd packet command.
Step 1 |
enable Example:
Enables privileged EXEC mode.
|
Step 2 |
bfd-template single-hop template-name Example:
Creates a single-hop BFD template and enters BFD configuration mode. |
Step 3 |
interval min-tx milliseconds min-rx milliseconds multiplier multiplier-value Example:
Configures the transmit and receive intervals between BFD packets, and specifies the number of consecutive BFD control packets that must be missed before BFD declares that a peer is unavailable. |
Step 4 |
interface type number Example:
Enters interface configuration mode. |
Step 5 |
interface gigabitethernet number Example:
Specifies the Gigabit Ethernet interface and enters interface configuration mode. |
Step 6 |
bfd template template name Enables the BFD template. |
Step 7 |
end Example:
Exits interface configuration mode and returns to privileged EXEC mode. |
Step 8 |
debug bfd event Example:
Enables debugging information for BFD events. |
Step 9 |
debug bfd packet Example:
Enables debugging information for BFD packets. |
Step 10 |
monitor event-trace bfd event enable Example:
Enables the event traces for normal BFD events. |
Step 11 |
monitor event-trace bfd event all enable Example:
Enables the event trace filters for normal BFD events. |
Step 12 |
monitor event-trace bfd packet enable Example:
Enables the event traces for BFD packet events. |
Step 13 |
monitor event-trace bfd packet all enable Example:
Enables the event trace filters for BFD packet events. |
Step 14 |
show monitor event-trace bfd Example:
Displays event trace messages for BFD events. Use the critical , event , and packet keywords to display event trace messages for critical BFD events, normal BFD events, and BFD packet events, respectively. |
Device> enable
Device# configure terminal
Device(config)# interface FastEthernet 6/0
Device(config-if)# bfd interval 50 min_rx 50 multiplier 5
Device(config-if)# end
Device# debug bfd event
Device# debug bfd packet
Device# monitor event-trace bfd event enable
Device# monitor event-trace bfd event all enable
Device# monitor event-trace bfd packet enable
Device# monitor event-trace bfd packet all enable
Device# show monitor event-trace bfd critical all
Device# show monitor event-trace bfd event all
Device# show monitor event-trace bfd packet all
Device> enable
Device# configure terminal
Device(config)# interface GigabitEthernet 0/0/0
Device(config-if)# bfd interval 50 min_rx 50 multiplier 5
Device(config-if)# end
Device# debug bfd event
Device# debug bfd packet
Device# monitor event-trace bfd event enable
Device# monitor event-trace bfd event all enable
Device# monitor event-trace bfd packet enable
Device# monitor event-trace bfd packet all enable
Device# show monitor event-trace bfd critical all
Device# show monitor event-trace bfd event all
Device# show monitor event-trace bfd packet all
The following is sample output from the show monitor event-trace bfd command for a critical BFD event:
Device# show monitor event-trace bfd critical latest
Oct 2 10:57:25.173: BFD-DEBUG CRITICAL: V1 FSM ld:1 handle:1
Event:DETECT TIMER EXPIRED state:UP Rx Count:123 Tx Count: 120
Control Packets Rx:[Oct2 10:57:25.173][Oct2 10:57:25.173][Oct2 10:57:25.173]
Control Packet Tx:[Oct2 10:57:26.173][Oct2 10:57:27.173][Oct2 10:57:28.173]
Echo Rx:[-][-][-]
Echo Tx:[-][-][-]
Oct 2 10:57:25.173: BFD-DEBUG CRITICAL: V1 FSM ld:1 handle:1
Event:ECHO FAILURE state:UP Rx Count:123 Tx Count: 120
Control Packet Rx:[Oct2 10:57:25.173][Oct2 10:57:25.173][Oct2 10:57:25.173]
Control Packet Tx:[Oct2 10:57:26.173][Oct2 10:57:27.173][Oct2 10:57:28.173]
Echo Rx:[Oct2 10:57:25.273][Oct2 10:57:25.373][Oct2 10:57:25.473]
Echo Tx:[Oct2 10:57:25.273][Oct2 10:57:25.373][Oct2 10:57:25.473]
Note |
Logs all events that are logged using the debug bfd event command. |
Device# show monitor event-trace bfd event latest
*Oct 13 20:31:17.043: BFD-DEBUG Event: V1 FSM ld:1 handle:1 event:RX UP state:UP (0)
*Oct 13 20:31:16.945: BFD-DEBUG Event: V1 FSM ld:1 handle:1 event:RX INIT state:DOWN (0)
*Oct 13 20:31:16.150: BFD-DEBUG EVENT: bfd_session_created, proc:EIGRP, idb:Ethernet0/0 handle:1 act
*Oct 13 20:31:14.633: BFD-DEBUG Event: V1 FSM ld:1 handle:1 event:DETECT TIMER EXPIRED state:ADMIN DOWN (0)
Note |
Logs all packet events that are logged using the debug bfd packet command. |
Device# show monitor event-trace bfd packet latest
*Oct 12 05:30:46.849: BFD-DEBUG Packet: Tx IP:10.1.1.2 ld/rd:1/0
diag:7(Administratively Down) AdminDown cnt:21 (0)