Brocade Multi-Service IronWare Switching Configuration Guide (Supporting R05.6.00) - Manual (Page 954)

924 Multi-Service IronWare Switching Configuration Guide
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Configuring BFD for the specified protocol
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The holdover interval can be configured globally.
If the bfd holdover-interval is set to 20 seconds, when a notification is received from BFD that the
BFD session has moved to DOWN state, the system waits for 20 seconds before sending the BFD
session down notification to ISIS state machine. If the BFD session returns to UP state before the
20 seconds expires, the ISIS state machine is not notified that the BFD session flapped. Otherwise,
after 20 seconds the BFD session down notification is passed to the ISIS state machine. If BFD for
ISIS is disabled, the request to not use BFD for ISIS is passed to BFD by ISIS, BFD acknowledges
this request, and the BFD session is removed. If BFD is disabled, ISIS is notified and asks BFD to
remove the single hop BFD session on the interface.
To configure the BFD down notification delay, enter a command such as the following.
Brocade(config-isis-router)# bfd holdover-interval 10
Syntax: [no] bfd holdover-interval time-seconds
The time-seconds variable is a number between 0 and 20 seconds. The default is 0 seconds.
The no option removes the BFD holdover interval from the configuration.
Configuring BFD for BGP4
You can configure your device for BFD for BGP4. not supported on loopback, tunnel (including IGP
shortcut) and management interfaces.
BFD for BGP4 global configuration – Using this configuration, you can enable and disable BFD
BGP4 on a global level. In addition, you can use the global command to set revised default values
for the transmit interval, receive interval, and for the detection time multiplier for all BFD multihop
BGP4 sessions.
BFD for BGP4 at global, peer, and peer group configuration – Using this configuration, you can
enable and disable BFD for individual peers or peer groups. You can also change the values for the
transmit interval, receive interval, and for the detection time multiplier. If these values are not
specified at this level, they are obtained from the values configured at the global level.
BFD for BGP4, which is disabled by default, can be enabled or disabled at the global BGP router
level or for each individual peer or peer group. The hierarchy for BFD for BGP4 is as follows:
• Peer and peer group parameters can be configured but will not take effect until BFD for BGP4
has been enabled.
• Peer configurations will override global and peer group configurations.
• Peer group configurations will override global configurations
• The bfd-enable command under router bgp overrides all other BGP4 BFD configurations
Enabling BFD for BGP4 globally
By default, BFD for BGP4 is disabled and can be first enabled globally and then on each peer. To
enable BFD for BGP4 globally, enter commands such as the following.
Brocade# router bgp
Brocade(config-bgp)# bfd-enable
To disable BFD for BGP globally and terminate all BFD sessions used by BGP4, enter commands
such as the following
Brocade# router bgp
Brocade(config-bgp)# no bfd-enable