Setup Guide

Establishing Sessions for Static Routes for Nondefault VRF
You can also create nondefault VRFs and establish sessions for all neighbors that are the next hop of a static route.
To establish a BFD session for nondefault VRFs, use the following command.
• Establish BFD sessions for all neighbors that are the next hop of a static route.
CONFIGURATION mode
ip route bfd vrf vrf-name [prefix-list prefix-list-name] [interval interval min_rx min_rx
multiplier value role {active | passive}]
Example Conguration and Verication
The following example contains static routes for both default and nondefault VRFs.
Dell#sh run | grep bfd
bfd enable
ip route bfd prefix-list p4_le
ip route bfd vrf vrf1
ip route bfd vrf vrf2
ip route bfd vrf vrf1 prefix-list p4_le
The following example shows that sessions are created for static routes for the default VRF.
The following example shows that sessions are created for static routes for the nondefault VRFs.
Establishing Static Route Sessions on Specic Neighbors
You can selectively enable BFD sessions on specic neighbors based on a destination prex-list.
When you establish a BFD session using the ip route bfd command, all the next-hop neighbors in the static route become part of the
BFD session. Starting with Dell Networking OS release 9.11.0.0, you can enable BFD sessions on specic next-hop neighbors. You can
specify the next-hop neighbors to be part of a BFD session by including them in a prex-list.
Prex lists are used in route maps and route ltering operations. You can use prex lists as an alternative to existing access lists (ACLs). A
prex is a portion of the IP address. Prex lists constitute any number of bits in an IP address starting from the far left bit of the far left
octet. By specifying the exactly number of bits in an IP address that belong to a prex list, the prex list can be used to aggregate
addresses and perform some functions; for example, redistribution.
You can use the following options to enable or disable the BFD session:
• Permit – The permit option enables creation of a BFD session on the specied prex list or prex list range. The no permit option
enables tear down of the BFD session if and only if the ACL has no permit entry that shares the same neighbor.
• Deny – The deny option prevents BFD sessions from getting created for the specied prex list or prex list range.
For more information on prex lists, see IP Prex Lists.
To enable BFD sessions on specic neighbors, perform the following steps:
Enter the following command to enable BFD session on specic next-hop neighbors:
CONFIGURATION
ip route bfd prefix-list prefix-list-name
The BFD session is established for the next-hop neighbors that are specied in the prex-list.
• The absence of a prex-list causes BFD sessions to be enabled on all the eligible next-hop neighbors.
• You can use only valid IPv4 unicast address prexes in the BFD prex list. An erroneous IP prex in a prex-list causes the entire prex-
list to be rejected.
Bidirectional Forwarding Detection (BFD)
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