bfd & IPv6 on Cisco 4948E-E / IOS 15.2

Wed Jun 7 03:13:03 UTC 2023

I am attempting to setup bfd with IPv6 on Cisco 4948E-E running IOS 
15.2.  bfd on IPv4 works great, but I'm having troubles with IPv6 and 
spent hours on it.  The trouble exists whether I use OSPFv3 or BGP.  
Each side transmits, but the other side doesn't receive.  Same interface 
works fine on IPv4. Any and all help would be appreciated!

Using this on the interface of each switch:

  ospfv3 1 bfd
  ospfv3 1 ipv6 area 0
  ospfv3 1 ipv6 bfd
  bfd interval 500 min_rx 500 multiplier 40

#show bfd neighbors details
IPv6 Sessions
NeighAddr                              LD/RD         RH/RS State     Int
FE80::A2EC:F9FF:FE2B:B33F              68/0          Down Down      Te1/52
Session Host: Software
OurAddr: FE80::BA38:61FF:FE65:20BF
Handle: 1
Local Diag: 0, Demand mode: 0, Poll bit: 0
MinTxInt: 1000000, MinRxInt: 1000000, Multiplier: 40
Received MinRxInt: 0, Received Multiplier: 0
Holddown (hits): 0(0), Hello (hits): 1000(566)
Rx Count: 0, Rx Interval (ms) min/max/avg: 0/0/0 last: 23068067 ms ago
Tx Count: 566, Tx Interval (ms) min/max/avg: 756/1000/875 last: 268 ms ago
Elapsed time watermarks: 0 0 (last: 0)
Registered protocols: OSPFv3 CEF
Last packet: Version: 1                  - Diagnostic: 0
              State bit: AdminDown        - Demand bit: 0
              Poll bit: 0                 - Final bit: 0
              C bit: 0
              Multiplier: 0               - Length: 0
              My Discr.: 0                - Your Discr.: 0
              Min tx interval: 0          - Min rx interval: 0
              Min Echo interval: 0
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