Dell PowerSwitch S4820T Configuration Guide for the S4820T System 9.100.0 - Page 138
Viewing Physical Port Session Parameters, Disabling and Re-Enabling BFD
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Configured parameters: TX: 100ms, RX: 100ms, Multiplier: 3 Neighbor parameters: TX: 100ms, RX: 100ms, Multiplier: 3 Actual parameters: TX: 100ms, RX: 100ms, Multiplier: 3 Role: Active Delete session on Down: False Client Registered: CLI Uptime: 00:03:57 Statistics: Number of packets received from neighbor: 1775 Number of packets sent to neighbor: 1775 Number of state changes: 1 Number of messages from IFA about port state change: 0 Number of messages communicated b/w Manager and Agent: 4 Log messages display when you configure both interfaces for BFD. R1(conf-if-te-4/24)#00:36:01: %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) 00:36:02: %RPM0-P:RP2 %BFDMGR-1-BFD_STATE_CHANGE: Changed session state to Up for neighbor 2.2.2.2 on interface Te 4/24 (diag: 0) Viewing Physical Port Session Parameters BFD sessions are configured with default intervals and a default role (active). Dell Networking recommends maintaining the default values. To view session parameters, use the show bfd neighbors detail command. Example of Viewing Session Parameters R1(conf-if-te-4/24)#bfd interval 100 min_rx 100 multiplier 4 role passive R1(conf-if-te-4/24)#do show bfd neighbors detail Session Discriminator: 1 Neighbor Discriminator: 1 Local Addr: 2.2.2.1 Local MAC Addr: 00:01:e8:09:c3:e5 Remote Addr: 2.2.2.2 Remote MAC Addr: 00:01:e8:06:95:a2 Int: TenGigabitEthernet 4/24 State: Up Configured parameters: TX: 100ms, RX: 100ms, Multiplier: 4 Neighbor parameters: TX: 100ms, RX: 100ms, Multiplier: 3 Actual parameters: TX: 100ms, RX: 100ms, Multiplier: 4 Role: Passive Delete session on Down: False Client Registered: CLI Uptime: 00:09:06 Statistics: Number of packets received from neighbor: 4092 Number of packets sent to neighbor: 4093 Number of state changes: 1 Number of messages from IFA about port state change: 0 Number of messages communicated b/w Manager and Agent: 7 Disabling and Re-Enabling BFD BFD is enabled on all interfaces by default, though sessions are not created unless explicitly configured. If you disable BFD, all of the sessions on that interface are placed in an Administratively Down state ( the first message example), and the remote systems are notified of the session state change (the second message example). To disable and re-enable BFD on an interface, use the following commands. 138 Bidirectional Forwarding Detection (BFD)
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