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Configure BFD for VLANs
BFD on Dell Networking systems is a Layer 3 protocol.
Use BFD with routed virtual local area networks (VLANs). BFD on VLANs is analogous to BFD on physical ports. If you enable
the no routing protocol, and a remote system fails, the local system does not remove the connected route until the first failed
attempt to send a packet. If you enable BFD, the local system removes the route when it stops receiving periodic control
packets from the remote system.
There is one BFD agent for VLANs and port-channels that resides on RP2, as opposed to the other agents that are on the line
card. Therefore, the 100 total possible sessions that this agent can maintain is shared for VLANs and port-channels.
Configuring BFD for VLANs is a two-step process:
1. Enable the BFD globally. Refer to Enabling BFD Globally.
2. Establish sessions with VLAN neighbors. Refer to Establish Sessions with VLAN Neighbors.
Related Configuration Task
Changing VLAN Session Parameters.
Disabling BFD for VLANs.
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
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Bidirectional Forwarding Detection (BFD)