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Article Id 193818

This article describes local_diag code 0x03 and 0x23 in bfd log.

BFD session state UP -> Down local_diag = 0x03.

BFD session state UP -> Down local_diag = 0x23.

When dynamic routing flap, such as OSPF or BGP state UP -> Down, check the log, BFD state is UP -> Down log before related routing protocol log, and local_diag code is 0x03 or 0x23.


In RFC 5880, it is defining the code from 0 -8, 9-31 was unassigned.

Value BFD Diagnostic Code Name
----- ------------------------
0 No Diagnostic
1 Control Detection Time Expired
2 Echo Function Failed
3 Neighbor Signaled Session Down
4 Forwarding Plane Reset
5 Path Down
6 Concatenated Path Down
7 Administratively Down
8 Reverse Concatenated Path Down
9-31 Unassigned
For Fortinet, here is the define:
0x01: Local inactive timer expired.
0x03: Remote peer indicates it's down.
0x23: Remote peer indicates restarting.   


So for BDF local_diag code 0x03 and 0x23, customer needs to investigate remote peers other than FGT.