BFD Peers

A BFD Peer entry defines a relationship between this router and a peer so they can exchange BFD information and detect link faults.

Tip

For configurations with multiple peers which have similar settings, create a BFD profile with the common settings before creating peer entries.

BFD Peers are managed at Services > FRR BFD on the Peers tab.

The Peers tab contains a list of current BFD peers, if any, and controls to manage the entries (e.g. edit, delete). The Add button creates a new peer.

The remaining sections on this page cover the various options available when creating or editing a peer entry.

Peer Configuration

Peer Address:

The remote BFD peer address. The local and remote peer IP addresses must use the same address family (either IPv4 or IPv6)

Description:

A text description of this BFD peer.

Profile:

A BFD Profile from which settings will be used, unless overridden on this entry.

Options

Multihop:

Expect packets with a TTL value less than 254 indicating there is more than one hop between peer addresses. Also listens on the multihop port, 4784.

In most cases this option is not necessary, but certain configurations may require it, such as running BGP on loopback interfaces instead of an interface directly connected to a peer.

Warning

When using multi-hop mode echo-mode will not work, see RFC 5883 section 3.

Shutdown:

Enables or disables the peer administratively.

When the peer is disabled in this way an “administrative down” message is sent to the remote peer.

Source Address/Interface

Interface:

The interface on which to enable BFD.

Local Source Address:

The local address used as a source for BFD packets, if it differs from the primary IP address on Interface.

Advanced Options

Detect Multiplier:

A non-zero value that is, roughly speaking, due to jitter, the number of packets that have to be missed in a row to declare the session to be down. Must be between 2 and 255.

The remote transmission interval will be multiplied by this value to determine the connection loss detection timer. The default value is 3.

Receive Interval:

The minimum interval, in milliseconds, at which this router can receive control packets from a peer. The default value is 300.

Transmit Interval:

The minimum transmission interval, in milliseconds, for the router to send BFD control packets to peers. The default value is 300.

Echo Interval:

The minimum interval, in milliseconds, at which this router can receive echos from a peer. The default value is 50.

Echo Mode:

Enables or disables echo transmission mode. By default, this mode is disabled.

Warning

Echo mode is not supported on multi-hop setups, see RFC 5883 section 3.

Tip

FRR documentation recommends that the transmission interval of control packets to be increased after enabling echo mode to reduce bandwidth usage.

For example, increase Transmit Interval from 300 to 2000.