Does both end of BFD peer need to have the same Transmit and Receive Interval and contribute to BFD session flaps ?
BFD session flap observed and both ends of the BFD session has different Transmit and Receive Interval configured.
The BFD timers need not match on both ends. BFD FAQ
When the two ends of a BFD session have different intervals for transmitting and receiving packets, negotiation is performed between the two ends of the BFD session. The longer interval is used.
Both end times are maintained throughout the session and can be visible by executing "show bfd session extensive"
Snippet:
Detect Transmit
Address State Interface Time Interval Multiplier
10.0.225.117 Up reth5.271 2.550 0.850 5
Client BGP, TX interval 0.850, RX interval 0.850
Session up time 02:58:08, previous down time 00:00:25
Local diagnostic None, remote diagnostic None
Remote state Up, version 1
Replicated
Session type: Single hop BFD
Min async interval 0.850, min slow interval 1.000
Adaptive async TX interval 0.850, RX interval 0.850
Local min TX interval 0.850, minimum RX interval 0.850, multiplier 5
Remote min TX interval 0.300, min RX interval 0.300, multiplier 3 <<<<<<
Local discriminator 145, remote discriminator 1090519613
Echo TX interval 0.000, echo detection interval 0.000
Echo mode disabled/inactive
Remote is control-plane independent
Session ID: 0
10.0.226.117 Up reth5.272 2.550 0.850 5
Session up time 1d 12:58:23, previous down time 00:00:26
Remote min TX interval 0.300, min RX interval 0.300, multiplier 3 <<<<
Local discriminator 136, remote discriminator 1090519432
10.0.227.117 Up reth5.273 2.550 0.850 5
Session up time 1d 23:25:48, previous down time 00:00:26
Remote min TX interval 0.300, min RX interval 0.300, multiplier 3 <<<<<
Local discriminator 141, remote discriminator 1090519435
10.0.228.117 Up reth5.274 2.550 0.850 5
Session up time 15:26:16, previous down time 00:00:28
Local discriminator 144, remote discriminator 1090519435