Administrator Guide

Establish Sessions with VLAN Neighbors
To establish a session, enable BFD at interface level on both ends of the link, as shown in the following illustration. The session
parameters do not need to match.
Figure 15. Establishing Sessions with VLAN Neighbors
To establish a BFD session with a VLAN neighbor, follow this step.
• Establish sessions with a VLAN neighbor.
INTERFACE VLAN mode
bfd neighbor ip-address
View the established sessions using the show bfd neighbors command, as shown in the following example.
R2(conf-if-vl-200)#bfd neighbor 2.2.3.2
R2(conf-if-vl-200)#do show bfd neighbors
* - Active session role
Ad Dn - Admin Down
C - CLI
I - ISIS
O - OSPF
R - Static Route (RTM)
V - VRRP
LocalAddr RemoteAddr Interface State Rx-int Tx-int Mult Clients
* 2.2.3.2 2.2.3.1
Vl 200 Up 100 100 3 C
Changing VLAN Session Parameters
BFD sessions are congured with default intervals and a default role.
The parameters that you can congure are: Desired TX Interval, Required Min RX Interval, Detection Multiplier, and system role. You
can change parameters per interface, if you make a conguration change, the change aects all sessions on that interface.
CAUTION: When conguring BFD on VLAN or LAG interfaces, Dell Networking recommends a minimum value of 500
milliseconds for both the transmit and minimum receive time, which yields a nal detection time of (500ms *3) 1500
milliseconds.
To change parameters for a session, use the following commands.
• Change session parameters for all sessions on an interface.
INTERFACE VLAN mode
bfd interval milliseconds min_rx milliseconds multiplier value role [active | passive]
To view session parameters, use the show bfd neighbors command, as shown in the example Changing Physical Port Session
Parameters.
Bidirectional Forwarding Detection (BFD)
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