I have a BFD configuration as follows:
trae@cr01a-vyos# show peer 192.168.253.1 { interval { receive 50 transmit 50 } multihop source { address 192.168.253.2 } } peer 192.168.253.3 { interval { receive 50 transmit 50 } multihop source { address 192.168.253.2 } } peer 192.168.253.12 { interval { receive 50 transmit 50 } multihop source { address 192.168.253.2 } } peer fd52:d62e:8011:fffe:192:168:253:1 { interval { receive 50 transmit 50 } source { address fd52:d62e:8011:fffe:192:168:253:2 interface dum0 } } peer fd52:d62e:8011:fffe:192:168:253:3 { interval { receive 50 transmit 50 } source { address fd52:d62e:8011:fffe:192:168:253:2 interface dum0 } } peer fd52:d62e:8011:fffe:192:168:253:12 { interval { receive 50 transmit 50 } source { address fd52:d62e:8011:fffe:192:168:253:2 interface dum0 } }
You can see that the peers do get created, but there's an additional IPv6 peer for each configured one:
trae@cr01a-vyos# vtysh -c 'show bfd peers brief' Session count: 9 SessionId LocalAddress PeerAddress Status ========= ============ =========== ====== 3593528133 fd52:d62e:8011:fffe:192:168:253:2 fd52:d62e:8011:fffe:192:168:253:3 up 982613625 fd52:d62e:8011:fffe:192:168:253:2 fd52:d62e:8011:fffe:192:168:253:1 up 3062145522 192.168.253.2 192.168.253.3 up 1513909278 unknown fd52:d62e:8011:fffe:192:168:253:3 down 3367798349 fd52:d62e:8011:fffe:192:168:253:2 fd52:d62e:8011:fffe:192:168:253:12 init 1380539671 unknown fd52:d62e:8011:fffe:192:168:253:1 down 2320718896 192.168.253.2 192.168.253.1 up 2529726712 unknown fd52:d62e:8011:fffe:192:168:253:12 down 4085521433 192.168.253.2 192.168.253.12 up
Here's what the two peers (one configured peer) created look like:
trae@cr01a-vyos# run show protocols bfd peer | grep -A17 'peer fd52:d62e:8011:fffe:192:168:253:1 ' peer fd52:d62e:8011:fffe:192:168:253:1 multihop local-address fd52:d62e:8011:fffe:192:168:253:2 vrf default ID: 982613625 Remote ID: 3545106482 Status: up Uptime: 34 minute(s), 11 second(s) Diagnostics: ok Remote diagnostics: ok Peer Type: dynamic Local timers: Detect-multiplier: 3 Receive interval: 300ms Transmission interval: 300ms Echo transmission interval: 50ms Remote timers: Detect-multiplier: 3 Receive interval: 50ms Transmission interval: 50ms Echo transmission interval: 50ms -- peer fd52:d62e:8011:fffe:192:168:253:1 local-address fd52:d62e:8011:fffe:192:168:253:2 vrf default interface dum0 ID: 1380539671 Remote ID: 0 Status: down Downtime: 34 minute(s), 19 second(s) Diagnostics: ok Remote diagnostics: ok Peer Type: configured Local timers: Detect-multiplier: 3 Receive interval: 50ms Transmission interval: 50ms Echo transmission interval: 50ms Remote timers: Detect-multiplier: 3 Receive interval: 1000ms Transmission interval: 1000ms Echo transmission interval: 0ms [edit protocols bfd]
As you can see above, it looks like the two getting created have different local timers, even though I've configured it for 50ms for transmit and receive.