This will generally indicate some kind of link or interface problem between the two devices. Here is the Juniper article of all the items to check.
https://supportportal.juniper.net/s/article/M-MX-T-Troubleshooting-Checklist-BFD?language=en_US#BFD_flap
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Steve Puluka BSEET - Juniper Ambassador
IP Architect - DQE Communications Pittsburgh, PA (Metro Ethernet & ISP - Retired)
http://puluka.com/home------------------------------
Original Message:
Sent: 04-19-2023 09:42
From: CRISTIAN CHIRATCU
Subject: BFD over BGP flaps from time to time with reason:Detect Timer Expiry
Hi,
BFD over BGP has the following issue. BFD flap from time to time , while bgp session is restored and also bfd session.
Do you know what to check? switch qfx5120. spine-leaf topology
logs:
DAEMON-4-BFDD_STATE_UP_TO_DOWN: BFD Session 172.31.101.4 (IFL 0) state Up -> Down LD/RD(16/23) Up time:7w0d 17:02 Local diag: CtlExpire Remote diag: None Reason: Detect Timer Expiry.
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CRISTIAN CHIRATCU
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