Dell PowerSwitch S4820T Configuration Guide for the S4820T System 9.14.1.0 - Page 174

To disable all VRRP sessions on an interface, sessions for a particular VRRP group, or for a particular VRRP session on an interface, use the following commands. • Disable all VRRP sessions on an interface. INTERFACE mode no vrrp bfd all-neighbors • Disable all VRRP sessions in a VRRP group. VRRP mode bfd disable • Disable a particular VRRP session on an interface. INTERFACE mode no vrrp bfd neighbor ip-address Configuring Protocol Liveness Protocol liveness is a feature that notifies the BFD manager when a client protocol is disabled. When you disable a client, all BFD sessions for that protocol are torn down. Neighbors on the remote system receive an Admin Down control packet and are placed in the Down state. To enable protocol liveness, use the following command. • Enable Protocol Liveness. CONFIGURATION mode bfd protocol-liveness Troubleshooting BFD To troubleshoot BFD, use the following commands and examples. To control packet field values or to examine the control packets in hexadecimal format, use the following command. • Examine control packet field values. CONFIGURATION mode debug bfd detail • Examine the control packets in hexadecimal format. CONFIGURATION debug bfd packet Examples of Output from the debug bfd Commands The following example shows a three-way handshake using the debug bfd detail command. R1(conf-if-te-4/24)#00:54:38: %RPM0-P:RP2 %BFDMGR-1-BFD_STATE_CHANGE: Changed session state to Down for neighbor 2.2.2.2 on interface Te 4/24 (diag: 0) 00:54:38 : Sent packet for session with neighbor 2.2.2.2 on Te 4/24 TX packet dump: Version:1, Diag code:0, State:Down, Poll bit:0, Final bit:0, Demand bit:0 myDiscrim:4, yourDiscrim:0, minTx:1000000, minRx:1000000, multiplier:3, minEchoRx:0 00:54:38 : Received packet for session with neighbor 2.2.2.2 on Te 4/24 RX packet dump: Version:1, Diag code:0, State:Init, Poll bit:0, Final bit:0, Demand bit:0 myDiscrim:6, yourDiscrim:4, minTx:1000000, minRx:1000000, multiplier:3, minEchoRx:0 174 Bidirectional Forwarding Detection (BFD)