Configuring High Frequency BFD
Overview
Bidirectional Forwarding Detection (BFD) enables networking peers on each end of a link to quickly detect and recover from a link failure. BFD detects and repairs a broken link faster than by waiting for BGP to detect the down link.
Peer link failure detection time via BFD is a minimum of three seconds, by default.
Starting with Avi Vantage release 20.1.1, the BFD parameters are user-configurable, for faster failure detection. This gives you the flexibility to choose the frequency of failure detection, as required.
High Frequency BFD Parameters
| Field | Description | Range | Default Value |
|---|---|---|---|
| minrx | The minimum rate at which the packets are received | 10-60000 (in milliseconds) | 1000 |
| mintx | The minimum rate at which the packets are sent | 10-60000 (in milliseconds) | 1000 |
| multi | The detection multiplier used in BFD.
For example, if multi = 3, The value of SE mintx = 500 ms The value of remote BFD minrx = 500ms, then the SE will be marked as Down if it doesn’t receive any packets from SE for 3*500 ms. |
3-255 | 3 |
Configuring BFD Parameters
The BFD parameters are configured in the VRF context.
To configure the same,
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Login to the Avi shell with your credentials.
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Enter the configure vrfcontext <vrfcontext name> as shown below:
[admin:abc-ctrl]: > configure vrfcontext global Updating an existing object. Currently, the object is: +----------------------------+-------------------------------------------------+ | Field | Value | +----------------------------+-------------------------------------------------+ | uuid | vrfcontext-1f42f9e5-2aee-4509-95c8-52a9d994fbe1 | | name | global | | bgp_profile | | | local_as | 65000 | | ibgp | True | | peers[1] | | | remote_as | 65000 | | peer_ip | 100.64.50.21 | | subnet | 100.64.50.0/24 | | md5_secret | | | bfd | True | | advertise_vip | True | | advertise_snat_ip | False | | advertisement_interval | 5 | | connect_timer | 10 | | ebgp_multihop | 0 | | shutdown | False | | peers[2] | | | remote_as | 65000 | | peer_ip | 100.64.50.3 | | subnet | 100.64.50.0/24 | | md5_secret | | | bfd | True | | advertise_vip | False | | advertise_snat_ip | True | | advertisement_interval | 5 | | connect_timer | 10 | | ebgp_multihop | 0 | | shutdown | False | | keepalive_interval | 60 | | hold_time | 180 | | send_community | True | | shutdown | False | | system_default | True | | tenant_ref | admin | | cloud_ref | Default-Cloud | +----------------------------+-------------------------------------------------+ -
A new parameter called bfd_profile is introduced within which the BFD parameters are configured. In the bfd_profile, enter the values for mintx, minrx, and multi.
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Save the configuration.
[admin:abc-ctrl]: vrfcontext> [admin:abc-ctrl]: vrfcontext> bfd_profile [admin:abc-ctrl]: vrfcontext:bfd_profile> mintx 1500 [admin:abc-ctrl]: vrfcontext:bfd_profile> minrx 1500 [admin:abc-ctrl]: vrfcontext:bfd_profile> multi 3 [admin:abc-ctrl]: vrfcontext:bfd_profile> save [admin:abc-ctrl]: vrfcontext> save
The BFD parameters are now configured as per the values entered.
The minimum timeout duration was 3 seconds in prior releases. From Avi Vantage release 20.1.1, the minimum timeout duration as low as 1.5 seconds is supported.