BFD Hardware Assist

Bidirectional Forwarding Detection (BFD) hardware assist support provides the functionality to run a BFD session in hardware. Effective failure detection requires BFD to run at high frequencies (using aggressive timers as low as 3 ms), which was not possible in the Software Mode because of CPU and ExtremeXOS restrictions.

Starting with ExtremeXOS 30.5, BFD hardware assist supports multi-hop.

To make BFD sessions run in the hardware, the following configuration is required:

L2 topology convergence time might affect the BFD sessions running at the shortest interval.

Unconfiguring loopback for BFD disables the hardware assist support. The supported shortest interval is 3 ms in hardware mode.

Sample configuration:

Configure the port 1 as loopback port dedicated for BFD:

#configure bfd hardware-assist primary loopback-port 1

To check the number of BFD sessions supported in the hardware and configured loopback port:

#show bfd
Hardware Assist Operational State         : Enabled(Loopback 
port not configured) 
Hardware Assist Primary Loopback Port     : 1 
Hardware Assist Secondary Loopback Port   : None
Maximum # of Hardware Assist Sessions     : 900

To find the session running the hardware:

#show bfd session detail
Neighbor       :          Local       :          
VR-Name        : VR-Default          Interface   : v1                  
Session Type   : Single Hop          State       : Down
Hardware Assist                 : Yes         

To see the hardware counters:

#show bfd counters
#show bfd session counters