BFD for Static Routes

To use BFD on a static route, both the firewall and the peer at the opposite end of the static route must support BFD sessions. A static route can have a BFD profile only if the Next Hop type is IP Address.
If an interface is configured with more than one static route to a peer (the BFD session has the same source IP address and same destination IP address), a single BFD session automatically handles the multiple static routes. This behavior reduces BFD sessions. If the static routes have different BFD profiles, the profile with the smallest Desired Minimum Tx Interval takes effect.
In a deployment where you want to configure BFD for a static route on a DHCP or PPPoE client interface, you must perform two commits. Enabling BFD for a static route requires that the Next Hop type must be IP Address. But at the time of a DHCP or PPPoE interface commit, the interface IP address and next hop IP address (default gateway) are unknown.
You must first enable a DHCP or PPPoE client for the interface, perform a commit, and wait for the DHCP or PPPoE server to send the firewall the client IP address and default gateway IP address. Then you can configure the static route (using the default gateway address of the DHCP or PPPoE client as the next hop), enable BFD, and perform a second commit.

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